I still have no idea why the heck your pit is open.
Every new player is falling in there at least once.
He will probably not fall in there again, because he learned from his mistake.
But to be honest, it's not his mistake, it's YOURS.
There is no official map where the pit is open, so of course he won't expect it to be in other maps.
And the worst thing about the pit is, that it's directly below the main position of the defending team. They are likely don't even see it, before it's too late.
I really don't know why you stick too this obviously bad idea of an open pit.
After falling in there, the player will think about how stupid the mapper is and how bad this map is and how bad it is designed and that his KPD is screwed and that it's not his mistake and so on.
I think you got my point. He'll probably not vote the map again in the next mapvote.
Since humans tend to remember negative impressions better then good ones.