OnTriggerEnter half working

When my spaceship hits and asteroid the OnTriggerEnter only ‘sometimes’ gets called. Other times I pass right through the object without the function being called.

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What I can’t figure out is why it sometimes DOES work while other times it doesn’t. Also it is completely random.

How large are the colliders in question and how fast are the objects moving? If the colliders are small’ish and the speeds are sufficient, it’s possible that on frame N you haven’t quite collided but on frame N+1 you’ve already moved completely beyond the collision. In that case, the collision will never be detected.