What some emails, checks and balls do Crossword Clue

 The answer to the crossword clue "What some emails, checks and balls do" is BOUNCE.

To bounce means to be returned, typically because of an error or because the recipient is unavailable. This can happen with emails, checks, and balls.

In the case of emails, a bounced email is one that is returned to the sender because the recipient's email address is invalid or because the recipient's mailbox is full.

In the case of checks, a bounced check is one that is returned to the issuer because the account does not have enough funds to cover the check.

In the case of balls, a bounced ball is one that hits the ground or another object and then returns to the player.

I hope this helps!