Corrosion vs short circuit: how liquid damage actually kills a board

A short circuit happens fast — water bridges two points on the board that were never meant to touch, and current flows somewhere it shouldn't. This can kill a component instantly, which is why powering on a wet phone is the single worst thing you can do to it.

Corrosion is slower and sneakier. Minerals in the water react with the metal contacts and traces over hours and days, building up a crust that breaks connections gradually — a phone can work fine for a week after a spill and then stop charging, or lose its camera, as corrosion finally severs a trace.

This is why we don't just dry a water-damaged phone and hand it back — we open it, clean every contact point ultrasonically, and inspect under magnification for early corrosion before it becomes a dead board.