>>30935458Power and reliability.
Kommo-o's real problem is that Ghosts, Bugs, Psychics, and Fairies are everywhere. It can't spam its STABs because it gets walled and checked by at least two mons of any OU team. It's not powerful or fast enough to be worth using as a wallbreaker / holepuncher.
Every time you click a move with Kommo-o, you have to rely on blind prediction and 50/50s to do anything. It's not worth it when there are better, easier Specs mons such as Hydreigon, Greninja, Hoopa, Tapu Lele, Wishiwashi, etc.
