User blog comment:GAMEONBOI/How strong is deku/@comment-31780034-20181002025821

The reason is, it is 100% of his CURRENT Power. As his strength increases, so will his power output. That's why his 5% during the Stain Arc and the 5% during the Teacher vs Students Exam Arc are a bit different in strength. Another example would be the 5% he showed during Deku vs Kacchan Part 2; his 5% was drastically different from other showings, heck, his speed was incredible. This fight also shows that when his emotions get to point where he goes "crazy" his limiter is removed, or I guess I could phrase it where, his body gets used to his current strength and increases the limiter he already set? If that makes sense. Now, we're unsure how strong Prime All Might really is (Seeing the movie tomorrow, if anything i'll edit this comment after I've seen it). During the Overhaul Arc, precisely the fight between Deku and Overhaul, Deku's limiter was raised to 20%, keep in mind this is 20% of his CURRENT power. While 20% barely did anything against Overhaul, there's no saying it won't be useful later, hell, you could say it was the reason he won his fight against Gentle. Anyways, I got off track, the 100% Full Cowl we see Deku using against Overhaul isn't really him at maxium potential. It's more of a "This is 100% of what I can do right now!"

Hope that cleared some things up ^^