1-hit KO moves having no affect?

Question

Some 1-hit KO moves sometimes"it doesn't affect the" other Pokemon or else "it has no affect on" the other Pokemon
Why is that?

Answer 1

If you're a lower level than your opponent, OHKO moves will always fail. If you're higher level, the move has 30 accuracy but increases as the gap between levels increases ( eg if you're one level higher, it will have around 30% accuracy, if you're 70 levels higher it will have 100% accuracy ). When it doesn't hit, or you're lower level, it will always say it failed.

Comments

You don't have to be a higher level, just the same level. I know this because of my Excadrill.