When things like the Thorn bounty are tied to Crucible, bounties that penalize deaths, heck yeah people are going to leave. When connections are so bad the lag makes killing players impossible, heck yeah people are going to leave. When matches are so unevenly balanced one team immediately begins trouncing the other without hope of redress, heck yeah people are going to leave. That's just a few of the reasons, of course, and that only includes intended departures. Life emergencies, disconnects, etc. would also be included. Crucible is a competitive player mode where good sportsmanship is practically non-existent. Many players have the goal of forcing the other team to rage quit. Teabagging and in-game taunts through messaging are normal. Heck yeah people are going to leave.