I can’t stress enough how important it is to enjoy what you are doing. If you don’t enjoy playing poker, or get very easily stressed, when you are loosing some, why continue playing it? I know quite a few people who are playing poker just to get famous some day. Becoming a star is a very good motivation, but how are you going to get there, when you lack any passion for the game what so ever? I’m yet to see a guy who got famous just because he wanted to and not loving what he became famous for.
Fun is important, even very important if you want to succeed in what you are doing. Then again, too much fun will not get you anywhere either. If you want to achieve something, you also need to be considerate and serious enough to notice and learn from your mistakes. If you focus all your energy on playing without bothering to do anything else, you might realize at some point that you haven’t achieved much.
So if you want to become successful holdem player, you have to be balanced. Going too far in either direction will not do good for you. If you don’t enjoy the game, you might soon find that it is too boring to continue playing and if you are too busy having fun, you will not achieve much in the long run either.