If it's lopsided to the point of worthlessness, I'll quit a crucible match. Say there's a team of 3 or 4 just ape spawn farming and the team isn't even reasonable enough to try to stay alive to manage any form of consolidating efforts and just feed. That's not fun at all, so I might dip out. If, however, I can have some good practice during the loss, have some fun engagements, I wouldn't quit. To me the fun of a crucible game isn't the win or loss, that's pretty irrelevant. It's more about what type of engagements I can have.