As someone who has been late most of my life, I’ve kearned that almost everything takes 15 or 30 minutes longer than you think. And build in a buffer just in case. I even put events in my calendar as if they start 15 minutes sooner than they do.
And now, I have a friend who runs later than anyone I’ve ever known. Often 60-90 minutes late. So frustrating. So now I have her provide her own transportation. Strangely enough, she is timelier then when I used to pick her up.