>>19930299>why would someone willingly use Water-attacks on Gastrodon>why would someone willingly use Fire-attacks on Chandelure>why would someone willingly use Grass-attacks on Goodra>why would someone willingly use Electric-attacks on ElectivireThe point is that it's not willing you fucking moron. You catch them by surprise, or you trick them into not doing it at all.
Imagine this scenario: the opponent's got a low-health Jolteon. You've got a Gyarados out, with a M-Sceptile in the wings. The opponent could easily kill Gyarados with Thunderbolt, but then runs the risk of powering up M-Sceptile. So instead, they use Hidden Power Ice. This leaves them wide open to Gyarados's Earthquake, who easily tanks the attack because the opponent fucked up in prediction.
>tl;dr It's not the actual threat, it's the hypothetical threat 