How Did Krillin Get Stronger After Potential Unlock in DBZ?
Well the same could be said about Ultimate Gohan. The Elder Kai basically brought out Gohan's untapped potential. However, the  Ultimate Gohan in the Universal Survival arc is a lot stronger compared to the Ultimate Gohan in the Buu Saga. Even during the course of training, Picollo stated himself that Gohan could get a lot stronger.I believe a good explanation or the way to look at it would be this way. Fighter A is only using 75% of his power X when there is 25% of untapped power. However, the X can be modified by training. A good analogy would be comparing it Cell vs Gohan. Gohan's wasn't using all of his true power while fighting Cell in the start until he tapped into SSJ2. However, SSJ2 wasn't obviously the maximum level of strength Gohan could attain as he grew a lot stronger.