Failed or not failed harmonic pattern depends on the size of SL and TP. This means depends how you trade harmonics and where you position your SL and TP.
Also, failed pattern does not necessary mean lost money or lost opportunity. You can for example check this thread -> http://tradingarsenal.com/market-geo...-negation.html where trading failed Gartley pattern concept is presented.
If there are a lot of failed harmonic patterns, as kor4x says, does it means that harmonic patterns are not RELIABLE??. If so, the strategy would be to complement it with drapichrust is trying out with trusted "turns" at the Gann square of nine ???