Ditto to everything Vader wrote, and I'd like to add that too many bands these days don't know when it's time to hang it up. Just because people are willing to pluck down money see you play, doesn't mean you have to go out and tour. I have two friends at work who are seriously considering going to see the Stones play in Chicago. I wouldn't sit through a Stones concert in 2018 if you paid me. In fact, it's my opinion that the Stones haven't put on a really good show in decades. People talk about how great it would be if Zeppelin got back together and started touring. I say no it wouldn't, they would suck. Zeppelin figured out back in the 70's that it didn't matter whether they put on a great show or a crappy show, all the trained seals in the audience would be slapping their flippers together just the same. I think Van Halen should stay retired and never tour again. Same goes for all the huge bands back in the day. They can't play or sing anymore, it's embarassing. All they're doing is prostituting themselves for money. Just my opinion, I wish those old bands would choose dignity over money.
Btw, I'm not talking about bands that can still put on great shows, there are some out there. Just the ones that suck, yet keep on touring.