The most important thing is each kid's passion and work ethic. If he put his stick down after his last game in May, and hasn't picked it back up, he maybe doesn't want to play all year. Or he's not ready for that pressure. Not a dealbreaker at this age. At the end of 8th grade....yes.

Also, there's "playing all year" and PLAYING ALL YEAR.

Most coaches and pediatricians agree:
1) Some "time off" is good
2) It doesn't hurt to pick up the stick a few times a week in the off-season (Aug-January) ("playing all year")
3) Huge benefits to focusing on different sports in fall and winter, maybe working out with lax on their day off their winter sport.

That said, there are some clubs that want you playing lax 3-5x per week, plus 4 fall tourneys, plus a fall box league, plus a winter box league, plus 5-6 summer tournaments. "PLAYING ALL YEAR." I'm not really confident that's good for most athletes under 15 years old. And it's offered/required by some clubs.