Why can’t some high rated chess players teach chess successfully?
I believe that in order to be a good teacher, he or she needs to be proficient in the material he teaches by playing it himself many times.

Stop crying. The world does not have to slow down for you guys. There are chess intellectuals that appreciate the content that is out there that you guys deem "hard to understand" and there is always a Mato Jelic (which I loved when I was starting out) that will players with a different level of ability.

Top players get to where they are by playing other top players. Teaching only works at lower levels where teachers can help to guide the learning, but eventually it is down to the calibre of the students and the opposition.

The importance of self-study increases with strength, but that does not diminish the importance of quality instruction. It is not a coincidence that so many titled players have turned to Dvoretsky's books for study. There's a lot of work that goes into playing at the higher levels. The play often motivates the work, but the work still needs to be done and a good trainer can help with devising an effective study plan.

Ever hear the expression "Those who can't do, teach."
I think Bobby Fischer, in his prime, summed it up best. When asked how to get good at chess he replied "Read 1000 books on chess, then read them again" Fischer, who was self taught, became a Grandmaster without a teacher. He did, however read 4000 books on chess.
Today, with computer programs to show all the infinite opening lines, it's much easier to learn.
Top rated players don't have the time nor should they be expected to teach, unless they have the desire. However, bear in mind top rated players are so far above the average player, it's like asking why Michael Jordan doesn't teach basketball. The things that average players need to learn are second nature to them. They can throw out cliches like 'Don't bring your Queen out early" or "Control the center", but knowing all the opening lines for 5 to 10 moves isn't something you can or should learn from a teacher. It's just too time consuming. I have been playing for 50 years, but never had the patience to learn all the openings. I will say this though.. TACTICS is the best teacher I ever ran across.
Most of the posts in this topic are bad, but this one gets just about everything wrong.
@OP, the short answer is (as only a few have been able to point out) teaching itself is a skill.

Imo, not only some, but most and the answer to your question, is intuition. It is because they use intuition in their games and intuition isn't something that can be taught. Of course, they can teach a beginner, as we can, but basic principles can go you so far. At some level (which actually is very low), it is all about who has the best intuition and calculation skills and that isn't easily teachable.
I am a very low rated player, but I don't think that anyone can teach me much, not even good teachers. Because, nobody can teach me visualization, calculation and intuition. Maybe, if I was a 7 year old, but not now.

1) chess is skills. So, it has to be learnt by practice.
2) titled players have no idea about the problems faced by beginners especially adult beginners. Their advice to beginners is counter productive most of the times.
3) at lower levels, coaches and books are more of a hindrance than help. So many people try so many coaches and books but their ratings remain unchanged.
4) chess knowledge(opening and endgame) is freely available.

Because, nobody can teach me visualization, calculation and intuition. Maybe, if I was a 7 year old, but not now.
It is true that no one can teach you these skills but it is also true that there are methods to increase them.
The main problem is no the lack of teacher but the lack of the necessary determination and dedication.
Are you willing to sit on a real board for an hour and practice endgames with absolute concentration? Can you do that consistently for at least 12 months?
Are you willing to play long time control games and analyse thme thoroughly after they end?Can you do that consistently for all your life?
Are you willing to look for better players that will offer tough instructive games and not rely on the random choice of the system?
If you are dedicated and determined enough , you don't need any teacher .You only need a guy that is good enough to answer your questions , explain you what you don't understand and help you with the analysis of your games.
The point is , no teacher can help you because 95% of the work must be done by you anyway.
Blam!! Piercing. To the bone. Or heart.
I think it was Botvinnik who said that teachers/coaches have to help students work it out themselves. Or something to that effect.
Chuddog says the same thing.

Because, nobody can teach me visualization, calculation and intuition. Maybe, if I was a 7 year old, but not now.
It is true that no one can teach you these skills but it is also true that there are methods to increase them.
The main problem is no the lack of teacher but the lack of the necessary determination and dedication.
Are you willing to sit on a real board for an hour and practice endgames with absolute concentration? Can you do that consistently for at least 12 months?
Are you willing to play long time control games and analyse thme thoroughly after they end?Can you do that consistently for all your life?
Are you willing to look for better players that will offer tough instructive games and not rely on the random choice of the system?
If you are dedicated and determined enough , you don't need any teacher .You only need a guy that is good enough to answer your questions , explain you what you don't understand and help you with the analysis of your games.
The point is , no teacher can help you because 95% of the work must be done by you anyway.
Woah! I agree with you!
But, of course, some disagreements:
1) Actually, it is not really lack of determination...etc. It comes down to priorities and cost, benefit analysis. How much time and effort are you willing to put on chess? And what monetary benefit are you going to get out of it? Chess pays very badly. So, there is not much reason to put extreme amounts of time and effort into it unless you think you are going to be the top 10 chess player(who are paid well). Then, there may be some reason to put in the effort. Otherwise, it is a waste of time to put in too much effort by going out of the way. So, people keep it at the level of a hobby. And at the level, there is only so much time and effort you can invest.
2) titled teachers and books at lower levels are not only not needed but are a hindrance. Frequently, the things they suggest are counter-productive. For example, the openings which are suggested as good are generally 'good' because they give an equal play. Openings which are suggested as unsound are the ones with one or two traps. But, these traps will work at lower levels. And thus they are very useful tools. Similarly, gambit play or even extreme gambit play is very useful at lower levels. These two things that I have pointed out could be applied to upto 2200 level atleast. In short, the things that don't work at higher levels work beautifully at lower levels. And titled coaches and books avoid these things not to appear cheap.
3) long formats are useless time waste for beginners. Bullets is also not good for beginners. Blitz and Rapid are the best way to learn for beginners. Even in those two formats, Blitz is the best format for beginners. Beginners lose to basic blunders or opening traps. The best and fastest way to learn to avoid these two is blitz. (One of the mistakes of titled player coaches is they instruct low rated players to play longer games.)

Because, nobody can teach me visualization, calculation and intuition. Maybe, if I was a 7 year old, but not now.
It is true that no one can teach you these skills but it is also true that there are methods to increase them.
The main problem is no the lack of teacher but the lack of the necessary determination and dedication.
Are you willing to sit on a real board for an hour and practice endgames with absolute concentration? Can you do that consistently for at least 12 months?
Are you willing to play long time control games and analyse thme thoroughly after they end?Can you do that consistently for all your life?
Are you willing to look for better players that will offer tough instructive games and not rely on the random choice of the system?
If you are dedicated and determined enough , you don't need any teacher .You only need a guy that is good enough to answer your questions , explain you what you don't understand and help you with the analysis of your games.
The point is , no teacher can help you because 95% of the work must be done by you anyway.
Just wanted to say that I really like your post and all you say sound really logical and true to me.
Of course, the implementation of all those is really hard and impractical (if not illogical) for most of us. Willing to try (like avoiding bullet, studying some and analyzing some and not just playing), but certainly not to the extend you correctly portrayed.