If you have for example rare teams in siege, most rares only strip a single buff, so if you would run bolster, would that be a viable target to be stripped but it just doing nothing or would it prio the other buffs.

Example->

Champ A has Bolster (protected shield), Stoneskin, Magma Shield

Champ B lets say Taneko, often used rare to strip buffs, strips 1 "random" buff from the target A.

How are the chances that it hits the stoneskin.

A: 50/50 bolster wont be taken into account. It will either Strip magma shield OR stoneskin

B: 33% Bolster is a viable target but nothing happens, so either stoneskin, bolster or magma shield will be hit.