Why did her neighbors go up on the roof?

M. Hi, Jane ... Say, are you OK? You’re looking a bit tired.
W: Oh, I am. It’s my neighbors.
M: Oh, so they’re acting up again, Huh?
W: Unfortunately, yes, they are.
M: Loud music?
W: Not exactly. You’ve been to my apartment, right?
M: Yeah. I’ve been there once. It’s a nice place.
W: Well, thank you. So you remember I live on the top floor. Well, last night, around eleven, my neighbors decided to go up on the roof of my apartment building.
M: The roof? Really?
W: Yeah. They had this guy in from out of town and they wanted to show him the view! Can you believe it? I was soundly asleep, and all of a sudden I heard "stomp, stomp, stomp!" They were walking around on the roof. It sounded like my ceiling was going to fall in.
M. So what did you do?
W: Well, after about ten minutes, I got dressed and went up there to tell them to be quiet. I was so mad. Then of course after that, I couldn’t go back to sleep.
M: Oh, don’t you hate when that happens? You can’t fall asleep, and then before you know it, it’s morning and the alarm clock is going off.