Have to ask, do you fly in, say, a Cobra?
Because given how small those things are, it's really, really easy to 'fly safe' in a Cobra, and not hit anything while docking. On the other hand, when your ship's height is juuuuuuuust barely smaller than the width of the entire docking slot, it becomes significantly less cut-and-dry. =P Chances are most of us can dock a Cobra with no issue of impact because it isn't remotely difficult.
But to bring the collision issue into more context, let's say you're out driving in a car, park in a parking lot and, when opening your car door, accidentally 'ding' the truck beside you.
And then the truck explodes.
That's kind of the issue here. =P Impacts that are very, very tiny, and aren't even collisions so much as light kisses, are making ships blow up.