@ DekiruTheNine actually it is not really a "multiplier" but an "accumulator", it accumulates the energy that exists in the users and increases the stock according to the time of use. The best proof of this is the quirk that AFO gave to Yoichi: "a quirk to store power", that is, what makes OFA so strong is the accumulation of energy from users with the key factor being the time it was used ( All Might being the one who used it the longest).