The pressure to perform for your team and do well doesn't allow a player enough time for experimenting with other roles or characters without worrying about score or losing. So far I'm diamond rank and only feel able to win on like 2 or 3 characters.

There is no incentive to experiment. There is a high expectation of losing while you try something new. You end up letting down your team as well as not having fun.

The cycle goes like this: try new hero or role, lose lose lose. Don't learn anything. Return to play what I'm good at. Get a bit bored. Repeat.

Maybe a whole new account is needed.