The Sicilian doesnt follow the main opening príncipe: "occupy the center with your pieces". It is a wing opening (defense), so it is more complex in essence than 1...e5
The Sicilian for Children and Beginners - Myths and Facts:
"For players with very limited experience, I recommend using openings in which the play can be clarified at an early stage, often with a degree of simplification. ... the Sicilian Defence ... normally leaves you with little room to manoeuvre and is best left until your positional skills develop." - IM John Watson (2010)
"... These days ....c5 is more popular than ....e5, so who's to say that the lessons learned in e5 are somehow more valuable? It was by far the most popular opening in the past, but it's no longer the case. The lessons in the Sicilian, as irrational as they may seem to a relative newcomer, are very important to learn and who's to say that this type of action packed/dynamic chess is not just as good a way to start as the more classical style of chess. ..." - IM Greg Shahade (2012)
if a player succeeds in obtaining full development for all his forces ahead of his opponent he may feel fully satisfied with his work, this should outweigh any other consideration in the students mind (capablanca, chess primer)
so basically forget about specific openings and put your trust in the general chess opening principles
A true beginner should just focus on good piece development, COMPLETING development, and not throwing away all their pieces. Worry about specific openings down the road when you actually have some clue what your doing. Your fellow beginner opponents will not be playing 20 book moves in a row and once your not in a book position, you're just playing chess after that.
@Pfren Do you remember when you wrote how the Bowlder (sic) attack can be lethal against the Sicilian, and referenced a game where your much lower rated opponent got a completely winning position against you by playing 1.e4 c5 2.Bc4? What happened was, you blundered because you didn't see a tactic and your opponent in turned missed that the tactic was there, so you ended up winning. The post I refernce is here, post #65
With all due respect sir, you and your opponents seem just as clueless as you imply everyone else is. I daresay if you're missing simple tactics like that in a game you better put the opening psychosis aside. Openings don't affect someone's development, development comes from doing tactical puzzles and reading books on endgame and strategy. That anyone shouldn't play the Sicilian or any other opening out of fear it will stymie their development is ridiculous.
By the way, GM Roman Dzindzichashvili recommends the Accelerated Dragon in his Black repretoire book for all levels, and he's about as classical of a player as you can get.
Many reasons, maybe it looks fun/interesting to them and they want to try it.
I was watching a video series done by Hou Yifan talking about her career so far. It starts out with her showing some games from when she was a kid, guess what all the Chinese kids were playing? Sicilians. Perhaps the stodgy "you must play 1...e5" thing isn't a part of Chinese culture. There are some tremendously strong tacticians coming out of China these days I've heard.

Why would beginners want to play the Sicilian anyway.
Personally, everyone at my hs played e4 and everyone else responded e5. Playing c5 threw them off and that was enough of a reason for me. Now, I'm still a novice player only playing a few games in whatever spare time I have during college. Over time, the opening grew onto me, and I just play it because it's what I'm most comfortable with.
I'm no coach, but I was thinking along the lines of Pfren. My main complaint against it would be you should understand the rules before experimenting with the exceptions. In the Sicilian you often fall behind in space and development willingly for example.
Other than not knowing how to recognize or exploit such an advantage when it appears, you may even get some bad impressions like development and space isn't so important at all (instead of the truth, which is more like a continuum ranging form critical to unimportant).
A lot of things in chess are like that, on a continuum. But to have a good feel for when things matter and when they don't matter you need to start with the basics and attempt to strictly follow the "rules" of good moves (like centralization and center control) even if to your eyes it doesn't seem so important. If you start in the middle where sometimes it matters and sometimes it doesn't then it's a lot harder to get a feel for the game.
Many reasons, maybe it looks fun/interesting to them and they want to try it.
I was watching a video series done by Hou Yifan talking about her career so far. It starts out with her showing some games from when she was a kid, guess what all the Chinese kids were playing? Sicilians. Perhaps the stodgy "you must play 1...e5" thing isn't a part of Chinese culture. There are some tremendously strong tacticians coming out of China these days I've heard.
"Showing some games from when she was a kid"
I bet she wasn't a beginner though. "As a kid" people can rated over 2200. A beginner (a real beginner) is under 1000.
I think it's mostly because the Sicilian is a very tactical opening, and beginners don't usually have a good understanding of tactics, so coaches recommend that beginners play 1...e5 (often leading to Ruy Lopez) which is more positional.
I think it's more the opposite actually :p
And I don't know any good coach who would advise a beginner to avoid tactics.

Beginners are discouraged from playing sicilians early simply because they arent good in the areas that sicilians require one to be good in to play sicilians well , with success . I started off playing sicilians as a beginner due to Fischer's influence and I was murdered in almost every game . I changed to a different opening and only started playing sicilians again after I reached 2000 otb rating ... suddenly I had much better success in sicilians .

Oh, wait... Adrian is not American. Does he really count as a trainer, or not?
Rather than having a pop at Americans, it would be more useful to the Thread to tell us what Mihalchisin's reasoning was?
@Reb, wasn't that opening that took you to 2000 level the Alekhine? That's not very classical is it? How did you ever make it to National Master by just playing things like the Sicilian and Alekhine and not ever having 1...e5 as a staple to your repertoire?
@Pfren No, you clearly can't grasp that you're still missing basic tactics in your games. Perhaps you should take your own advice and stick with 1...e5 for a bit longer until you're ready for the Sicilian and can face White's critical 2.Bc4 without blundering. I find your advice rather contradictory, you've provided a clear example that the vast majority of chess games are decided by tactial vision and calculation, not the opening. Yet you persist with your idea that playing a particular opening is the key to success.
By the way I'm a 1.e4 player and play the double king's pawn from the White side, as I'm sure many other Sicilian players do. One of my favorites to play against it is the Danish Gambit, and I can scarcely think of a more "open opening" than that. This is something else, the Sicilian is only one fraction of anyone's overall repertoire, which makes the idea that people shouldn't play it even more ridiculous.
I'm seen Adrian Mikhalchishin and his products on 1.e4 e5, as well as his recommendation that people play it. Yet I've not heard or read anyone him specifically saying the Accelerated Dragon should be avoided. The Accelerated Dragon is a fantastic opening for anyone because it can be very positional with the Maroczy Bind, but it can also be more tacical with the 5.Nc3 lines. Of course, we're not very likely to get this opening on the board as there's a wide world of anti-Sicilians out there which lead to varied and rich positions, and often positions which are more open that the ones I see arising after 1.e4 e5. I watch people playing Italian and Ruy Lopez games and a lot of the time the position looks closed to me. But what do I know, I'm not an expert in it, maybe it is good for beginners to be playing Petroffs and Berlin defenses all the time, or spending hours and hours getting their Marshall Gambit theory down. Only after this can be they be ready for the Sicilian. Of course, I jest. Actually if any significant improvement comes from playing 1...e5 by itself, it's from White players like me who play the Danish and create a truly "open game" for the edification of both parties.
As a final note I must say I like GM Mikhalchishin and your impression of Americans is wrong. What do you think Americans are ultra-patriotic xenophobes who dismiss anyone who isn't American? I'm not at least, and many others here aren't. I'm not interested in countries or politics. Don't make assumptions of me just because I happened to be born within a certain set of imaginary lines.

OP is clueless. Missing a tactic in your game isn't a reason for a statement such as "e5 improved tactical skills" to be invalidated. Carlsen's Kd2 vs Anand was a huge blunder but obviously that guy just can't see tactics and needs to work on his tactical vision. I'm sure you saw it though, (after engine evaluation of course.) Someone's personal record with an opening or idea has no bearing on their advice to others on that opening, especially beginners. I have a great record with the Czech Benoni yet I wouldn't recommend it to anyone because it's pretty shady.

The Maroczy Bind is a pain to play from the black side, that alone should be enough reason to not use the Accellerated Dragon.
Although I would be interested in hearing from pfren what that non-American grandmaster has to say about it.
i agree with these facts but the sicilian is quite complex... and white can play a crapload of openings against it depending on which variation the beginner plays:
Grand-Prix (Against all)
Open Sicilian (Against All) this includes the checkover,Prins etc..
Rosollimo (if i spelled it correctly)
Closed Sicilian (Against all)
Yugo-Slav Attack (Dragon)
Fischer-Sozin (All)
Also the theory behind every move in the Opening Stage (15-20 moves) isn't very small.
Also there are some not-so simple exchange sacrifaces in the sicilian, example in the dragon and in the Najdorf (which for a sicilian player is essential to know), Sicilian is Complicated as i said because first the Guy playing it has to have some decent positional understanding (Looking out for weaknesses,Playing in the center the correct way etc) which most beginners don't have Also in the Open Sicilian including in others he has to play very actively(if i spelled it correctly) which most beginners don't do, if they don't play actively they will get a middlegame position , in which they don't know what to do. In the sicilian you control the center from the side. Beginners need something simple like playing e5 against e4 and playing d5 against d4 e5 is much better for a beginner because:
- No Very Complex Theory.
- Simple (Develop Pieces,get king safe, attack opponet s' king)
- Its Tactical (So by playing tactical games you get better at tactics)
If you don't like the sicilian defense, the sicilian pizza is good..

@Reb, wasn't that opening that took you to 2000 level the Alekhine? That's not very classical is it? How did you ever make it to National Master by just playing things like the Sicilian and Alekhine and not ever having 1...e5 as a staple to your repertoire?
@Pfren No, you clearly can't grasp that you're still missing basic tactics in your games. Perhaps you should take your own advice and stick with 1...e5 for a bit longer until you're ready for the Sicilian and can face White's critical 2.Bc4 without blundering. I find your advice rather contradictory, you've provided a clear example that the vast majority of chess games are decided by tactial vision and calculation, not the opening. Yet you persist with your idea that playing a particular opening is the key to success.
By the way I'm a 1.e4 player and play the double king's pawn from the White side, as I'm sure many other Sicilian players do. One of my favorites to play against it is the Danish Gambit, and I can scarcely think of a more "open opening" than that. This is something else, the Sicilian is only one fraction of anyone's overall repertoire, which makes the idea that people shouldn't play it even more ridiculous.
I'm seen Adrian Mikhalchishin and his products on 1.e4 e5, as well as his recommendation that people play it. Yet I've not heard or read anyone him specifically saying the Accelerated Dragon should be avoided. The Accelerated Dragon is a fantastic opening for anyone because it can be very positional with the Maroczy Bind, but it can also be more tacical with the 5.Nc3 lines. Of course, we're not very likely to get this opening on the board as there's a wide world of anti-Sicilians out there which lead to varied and rich positions, and often positions which are more open that the ones I see arising after 1.e4 e5. I watch people playing Italian and Ruy Lopez games and a lot of the time the position looks closed to me. But what do I know, I'm not an expert in it, maybe it is good for beginners to be playing Petroffs and Berlin defenses all the time, or spending hours and hours getting their Marshall Gambit theory down. Only after this can be they be ready for the Sicilian. Of course, I jest. Actually if any significant improvement comes from playing 1...e5 by itself, it's from White players like me who play the Danish and create a truly "open game" for the edification of both parties.
As a final note I must say I like GM Mikhalchishin and your impression of Americans is wrong. What do you think Americans are ultra-patriotic xenophobes who dismiss anyone who isn't American? I'm not at least, and many others here aren't. I'm not interested in countries or politics. Don't make assumptions of me just because I happened to be born within a certain set of imaginary lines.
That seems a bit unfair to denigrate pfren's opinions on openings because he missed a basic tactic. Certainly the charge for him to work on his tactical vision is completely unjustified since everyone blunders, even Carlsen.
Conversation from a kid's chess class:
Kid: "I want to play the Sicilian."
Instructor: "No, you must play 1...e5. The Sicilian is too complex of an opening for you."
Kid: "But you play the Sicilian."
Instructor: "Yes, but I'm better and more sophisticated than you. When I was a kid I didn't play the Sicilian either, because I was told not to just like you are being told. Thus from a young age I got the impression that children and beginners had no right to play the Sicilian, and the thought of them doing so now offends me."
The Sicilian for children and beginners - Myths and Facts:
Myth: Beginners shouldn't play the Sicilian because Sicilian players just memorize a ton of theory.
Fact: Of all the defenses to 1.e4 the Sicilian player is least likely to get their opening on the board at club level, where they will instead play against a plethora of dubious anti-sicilians led by the most popular 2.Bc4. Thus at below master level the Sicilian is actually the least theoretically intensive opening there is. Despite this all the 1...e5 players spending hours and hours studying the Berlin or Marshall Gambit continue to look condescendingly on Sicilian players for relying too much on theory.
Myth: Beginners shouldn't play the Sicilian because it's too complex.
Fact: Chess is a complex game in all it's facets. If people should stay away from something because it's too complex they may as well not play chess at all.
Myth: Beginners shouldn't play the Sicilian because their king will come under attack.
Fact: The Black king may or may not come under attack depending on which anti-sicilian or Open Sicilian variation is chosen. And the opposite side castling situations which people perpetuationg this myth refer to are double edged with White's king often coming under attack as well. As with the previous myth, if people are to avoid an opening because their king may come under attack they may as well avoid the game of chess. Furthermore defense and counterattack in chess are important skills for beginners to learn.
Myth: Beginners shouldn't play the Sicilian because it doesn't teach how to control the center like 1...e5 does.
Fact: The entire concept of the Sicilian is based around controlling the center and getting a central pawn majority.
Ultimate Fact: There is no reason for anyone at any level who wants to play the Sicilian not to do so.