In poker, consistency matters because the long term matters.  You are either playing a certain situation profitably over the long term or you aren’t.

New poker players are supposed to play “bad” and unprofitable poker.  And as a seasoned poker player, you are supposed to have developed the tools necessary to exploit their mistakes over the long term.  They are doing their job by playing unprofitably, so why aren’t you doing yours?  Is it possible that you don’t know how to truly exploit players’ mistakes?