Failing to break the disguise of an individual, should generally leave someone thinking they're just another undisguised person. Unfortunately the OOC " " and failed roll are sometimes taken as meaning re-roll in the next 10 minutes to try and break the disguise again, which seems a little excessive and does not feel very much in the spirit of RP in general.
My suggestion it to add an in game day, or so, cooldown for re-looking at the same disguised person, per disguise (so if they changed it within the cooldown, they can be re-examined), to help curtail this behavior and prevent 'stalling' to keep people around just long enough to re-examine them.
Otherwise, checking them out again because they seem interesting, or you're just a curious/forgetful person, or some decent time has passed, seems fine.
