Then stop thinking about the meta-level if "I like this, I like that, am I more talented at this, am I more talented at that" etc. etc. and you just force yourself to work on something.

Meanwhile, try lots of things, but spend most of your time polishing the fundamental skills you chose.

You have just one mind. The outside world only sees the output of your mind. It doesn't care that you really wanted to be good at maths or music or baseball or whatever but that your base urges and attention span made you switch around and robbed you of your time... all it cares about is the net result.

Therefore, it's up to you to conquer your fickleness.

GOOD LUCK :]