accident. Noun. something bad that happens that is not expected or intended and that often damages something or injures someone

It’s partly about it being preventable, but mostly about it being expected.

The expected outcome of drunk driving or speeding through crosswalks is hitting someone. It’s preventable by not driving drunk or not speeding.

A careful driver in the Netherlands killing a cyclist in a city center on a 20mph road is unexpected and fairly surprising - that would be a true accident. A drunk driver hitting someone on an American stroad is depressingly normal. It’s hard to call it an accident.