can’t win them all

(you) can't win them all

A phrase said, often as an attempt at consolation, when one has lost or failed to achieve a desired result, especially after previous success. "Them" is sometimes abbreviated as "'em." I know you're disappointed to have the lost the game, but you can't win them all, honey. A: "I'm sorry, I know you worked really hard and were expecting an A+." B: "Eh, can't win 'em all."
See also: all, win
Farlex Dictionary of Idioms.

can’t win (th)em all

tv. (one should) expect to lose every now and then. It doesn’t really matter. You can’t win them all.
See also: all, win
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • (you) can't win them all
  • can’t win em all
  • can't win them all
  • You can’t win ’em all
  • You can’t win them all
  • you can't win 'em all
  • you can't win them all
  • money, winning, etc. isn't everything
  • (something) isn't everything
  • winning isn't everything