1. A bad penny always turns up. 

2. 3 A bad penny always turns up. 

3. 25 I took long breaks away from training and would then reappear like the proverbial bad penny, as if I had never been away.

4. See: (one's) door is Always open (one's) nose is (Always) in the air a bad carpenter blames his tools a bad penny Always turns up a bad workman blames his tools a bully is Always a coward a poor craftsman blames his tools a rich man's joke is Always funny Always be on (one's) guard Always chasing rainbows Always the bridesmaid Always the bridesmaid