IDK. I don't usually PF and when I do I prefer to have a friend with me. While I'm never the first one to suggest leaving a broke party... I feel the itch to sometimes. Like when I see a co-healer SGE spamming Prognosis. Or a tank at P1S bringing True Flare to the group way too many times despite explanations between pulls. There was also the time where a guy asked to take a break just so he could do some fishing (???) which made me silently cranky.
I do disperse when more than 2 people leave. I feel like I waited adequately when I first joined for the group to come together, don't feel like waiting again.