How do you feel about people who are late when meeting up with you 90% or more of the time?
I've noticed that it's often people who are quite narcissistic in general who are chronically late. It's like they think their time's so much more important than yours that it's fine to just leave you waiting every time.
Obviously we're all late occasionally for reasons beyond our control. I'm talking about people who are late pretty much all of the time.