The errors I see the most are limping errors:
1. Limping to sitters
2. Limping with sitters
3. Limping buttons
4. Limp folding to short stacks
5. High blind limping
6. Open limping
The good news is the cure is very easy - just do not be the first player to limp.
Its still a mystery to me why players need to play bad hands out of position with no initiative and no fold equity
. To make these plays you basically have to not believe in fold equity, the power of position, and ICM.
I understand its ok if you have 6bbs(limp and go, limp and pray, or limp and outplay) or if you are Phil Helmuth playing AQo, with 18bb, in mid position against GTO pros.
When you limp with sitters you are basically trying to lose and hurt the whole table at the same time. You are voluntarily giving up your position and your fold equity - all with the hopes of inciting a limpathon and getting lucky and hitting with your trash hand.
Sitter limping causes your table to get less hands, win less of the sitters chips, and lose ground to other tables.
When you raise you are giving players a chance to fold and not pricing them in to play after you with position.