Originally Posted by J99
So this means that if a player is in the top 50, they have to be a full time ATP tour player, but it's not high enough for them to be a commitment player.
A "commitment player" just means that the guy has to play 4 ATP500 tournaments (or Monte-Carlo) in the calendar year in order to avoid a zeropointer in his rankings, AND in order to share the good $$$$$ from the bonus pool.
That's the only thing it means.
As for other top-50 players, usually they have enough with ATP world tour tournaments, sometimes they ask a wild-card in a challenger in their own country (Nieminen in Helsinki in a few weeks for instance, he plays that challenger nearly every year because that's the biggest tournament in his country) and/or if they get good money.