Why would anyone pay for membership on chess.com?

I'm not paying mostly because I don't normally buy anything online and I don't even own a credit card. I shop online only domestically if I can pay via my online bank.
I don't mind the ads. There is something flashing in the corner of the eye, but I guess most internet users' brains have got used to automatically filtering out ads, so you almost literally dont't see them. For other sites that are crawling with ads to the point that the sites don't even load properly, such as local news channels, I use another browser with adblock.
I also don't care about unlimited tactics. There are other sites where you can do unlimited puzzles for free - although I like the quality of the puzzles here better. But mostly because doing unlimited puzzles quickly turns into guessing and clicking.
I wouldn't mind more lessons, though. Some are very simple and short, so the entire course could be taken during one session.

@#65 thats exactly how feel. Haven't realized any ads until you talked about so I looked the screen to see something about ring tones never saw it realized it b4. Don't need unlimited tactics as I have it in other sites but never use it but chess.com gives 5 free limited which I do everyday. Imagine having unlimited I wouldn't even start doing it. now lessons that I could have used if I was a member going thru entire segments at a time.

The tactics trainer is the most necessary tool for me but there are many free sources of tactics. The free videos in other places usually aren’t as useful for learning as the ones available here after paying for a diamond membership. I believe the chess mentor lessons are unique to this site but I am not sure. It is a pretty valuable learning tool since it is a sort of automated replication of one on one coaching. Fairly reputable coaches explain positions they have chosen and have you play the next move. The comments on screen will be different depending on what move you pick. I am using the opening courses on it now to learn some new openings. If you put in serious study time and have a logical plan of improvement you can use these resources to increase your playing strength pretty rapidly. That’s how I improved when I first joined and how I plan on improving now that I just upgraded again.

Unless you are planning to play on chess.com for a month or a year everyday then yes. But for people like me, I am in and out of chess.

@SpiritoftheVictory What is Chess Mentor?
One game I enjoy here that I cannot find other places is the 4-player game
A Diamond Membership on Chess.com gives you unlimited access to:
* Live Games (Bullet, Blitz, Rapid and Variants) and Daily Games (1-14 days per move)
* Tournaments (Arenas, Swiss Events and Team Matches)
* Puzzle Training (Puzzles, Puzzle Rush/Puzzle Battle, and Daily Puzzles)
* New to Chess,Beginner,Intermediate,Advanced and Mastery Lessons
* Unlimited Video Library Course
* Full Game Analysis, Game Report and Review
* Live Analysis Boards
* Unlimited Practice (Drills)
* Unlock All Engines,Bots and Computers to Play against
* Opening Explorer, Databases, Opening Books, and Endgames
Yes it does
Given what I shell out for gold membership is much cheaper than spending on a coach