To fail in bed
is a more polite way to say that.
Just worth noticing that as in any area of life failing is one option, someone has said to err is human!
Okay a bit unrelated, anyway, people make of avoiding failing a way of life. Once, the one that was homeless, jobless, pennyless, etc was seen and depicted on the English literature and on the streets like "unfortunate". Today people dub one in this state like "a loser". Don´t wonder how this hurts people and make some angry.
Plus, if someone keep at it, someday will be eventually succesful. Just saying!