I voted "it Varies". I've been lucky in that all but one band I've been in since my forties have been with adults. People showed up prepared and ready to go because there wasn't time to just hang out party and act like you think you're a rock star. We all had careers, kids, lawns that needed to be mowed and wives or husbands that need attention. You be amazed at how much you can get done in a 2 1/2 hour practice with motivated band members.
I've been the leader of my own project now for almost 5 years. Again, with adults who want to get things done, no messing around because things outside the band, which are more important in the big picture of things need doing. Having said all that I'm tired of being a band leader. Especially a big band like mine, 9 total including the sound guy. That's a lot of schedules to keep track of and booking dates around vacations, work trips, family gatherings that must be attended. Luckily I have a list of three or four people for each instrument in the horn section I can call to sub. They're all sight readers and can just show up to the gig and knock it out of the park. But the one thing that bothers me the most as a band leader is the feeling of having 9 people in the boat and I'm the only one with my paddle in the water.
Back in the old days to promote a gig at a local bar you made flyers and posted them all over the neighborhood and in the bar and word of mouth and a bunch of other stuff. These days I can't even get my guys to "Like" "Share" and "Invite" their friends on Facebook. Seriously? Three or four mouse clicks is too much? OK, fine, whatever. I guess there's no perfect situation. We have 5 more gigs till the end of the year and I think I'm gonna end it and take a little break from the band thing then maybe look for something where I can just show up for rehearsals and gigs.