Its sad to say but from 4 years of playing travel ball I can say a lot has to do with who you know. Its a shame but 90% who you know and 10% player skill. If you were lucky enough to be a core player on a team from its inception odds are you will stay on that team from beginning to end. Which isn't a bad thing. There are those players that will knock the socks off the coaches at a tryout and will be added to a team. If its about even coaches will stay with the known player (player who has been with them over a kid who might have shown well at tryout only) there are also those players who a coach sees on another team that he will pursue and make deals with to get them to play for his team. Happens all the time.