Joined a group through group finder. Got vote kicked for being too low gear score or item level. Given 30 minute deserter cooldown. I did not not choose to leave I was kicked.
Blizzard added the deserter debuff soon after the release of the original RDF. Without it, tanks (especially, but others too) could essentially hold a group hostage: “Kick me or we don’t go anywhere.” Kicking the player allowed them to queue up instantly again to get a different instance while at the same time ratcheting up the hidden kick penalty for the rest of the group (players who kicked a lot eventually had to wait longer and longer before they could initiate a vote to kick). Adding the debuff to those who kicked solved this problem. It no longer mattered if the person refusing to do the dungeon was kicked or left on their own, they still got the same penalty regardless.
Yes it sucks for those who get kicked for doing nothing wrong, but the current implementation is much better overall than the alternative (and it is not a bug).