Well I'm very tempted to start ranting about the bassists I have to put up with, but I won't
in terms of mistakes live though, I don't think I've ever actually dropped/missed a beat. Sure I've missed hitting an actual drum or something, but that doesn't effect the timing of the song at all. Sometimes if I'm distracted, I might hit something out of time, but it's easily ignored, it doesn't upset the groove we're all playing to. I play with 3 different bassists, they all occasionally make mistakes, but they always get back on track with me.