burn your fingers

burn (one's) fingers

To suffer an unpleasant or ruinous consequence (especially the loss of money) for some action, often such that one becomes unwilling or uneager to do it again. During the boom times, countless would-be investors put everything they owned into shady investment deals, and most of them ended up burning their fingers badly.
See also: burn, finger

burn your fingers (or get your fingers burned/burnt)

suffer unpleasant consequences as a result of your actions.
1998 Times An American buyer remains a possibility, although it is not entirely clear why any would want to risk getting their fingers burnt twice.
See also: burn, finger