1- Ones that instill thinking along lines like this:
2- Forms, because they have nothing to do with fighting.
3- All the schools that do no sparring.
4- All the schools that do "sparring" with no gear. Sparring with no gear means that you can't go hard enough to get halfway decent.
5- All the practitioners that never spar hard enough to incur injuries. Injuries come with the territory of becomming a good fighter.
6- Ineffective techniques such as backfists that are included in forms and drills but hardly ever actually work against skilled oppoents.
7- Instructors who never fight or spar full force, but have "reputations" of being good, most of whom have never beaten a skilled opponent in their lives.
8- The same instructors who make brainwashed students believe that ineffective techniques are useful by demonstrating them at high force on the students while the students are complying.