Weather excluded:
-Injuries
-People who keep trying to talk to you
-Anyone who gets in the way of the session. Be it cops, people threatening to call the cops, or little kids using the skatepark as a playground without an attentive parent in sight
I work nearly 50 hours a week, so during the limited time I get to skate I want to get the most out of it. If something messes that up it bothers me a lot more than it used to, but that's not surprising. All the things I listed kind of sum up what you have to deal with trying to stay into skating while getting older and working full time so I guess it makes sense.
Edit: Format/grammar