This is the 468th most frequent Russian word.
уничтожили
"Destroyed" or "eliminated."
In this sentence, 'уничтожили' is used figuratively to signify how criticism severely affected someone's confidence, describing a metaphorical impact.
Сильная критика полностью уничтожила его уверенность.
Harsh criticism completely shattered his confidence.
Here, 'уничтожили' describes the act of getting rid of documents after a procedure, implying the action of making them cease to exist.
Ученые уничтожили старые документы после того, как оцифровали их.
The scientists destroyed the old documents after digitizing them.
Here, 'уничтожили' is used to describe the physical destruction of an object, in this case, a bridge, emphasizing its total ruin.