I've often noticed that as I am coming back to spawn, sometimes my character will automatically jump off too early. I'll end up in the pit instead of being in the spawn area.
I just noticed this post after already making a post about it, I also managed to capture a recording of it.
It's as @sickboy mentioned, it happens if you're facing backwards, or at least in a direction that will make you jump out when it automatically hops you off.
I initially thought it's because the shop is open, because every time it happened to me I had it open, but it turns out it's only based on the direction you're facing.