Having an otherwise useful superpower without any of the required secondary powers:
http://tvtropes.org/pmwiki/pmwiki.php/Main/RequiredSecondaryPowers
A good example being the guy that appears in 20:28 - 21:42 of this video:
If for whatever reason you don't want to / can't watch it, the guy has superspeed, but not super reflexes (first thing he does is run into a tree), stamina ("good grief, my muscles are going to be sore again tomorrow"), or control of inertia (he runs into a rainstorm at superspeed and it shreds him)