What's interrupting me when I am standing still?

Sometimes I go to interact with something, and then I just get interrupted for no reason.

I notice it happening mostly when I have a weapon drawn, so is the sheathing animation causing the interruption? If so that's stupid.

The server still thinks you're moving. There's a delay of a third of second built into the game, so you're quick you'll get caught by it.

Registration latency.

Ooooh now it makes sense.

Thank you, you two.