win some, lose some
It's not possible to win all the time, as in The coach was philosophical about our being shut out, saying “Win some, lose some.” This expression, generally uttered about a loss, originated in the early 1900s among gamblers who bet on sporting events. A variant, win some, lose some, some rained out, suggests that the idiom comes from baseball. Its figurative use dates from the 1940s. Also see you can't win 'em all.