win some, lose some

You win some, you lose some. AND You win a few, you lose a few. {Cliché} (=You cannot always succeed. Something that you say which means it is not possible to succeed at everything you do)— ~ ничего страшного — и на старуху бывает проруха; не везет в одном, повезет в другом

Example 1: Obviously I would have liked first prize but you win some, you lose some. (CIDI)

Example 2: The coach was philosophical about our being shut out, saying “Win some, lose some.” (thefreedictionary.com)

You can say this when you have not succeeded, to show that you are not discouraged.)
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. (thefreedictionary.com)

Also see
you [can't win 'em all]