Very rarely. Living in Minnesota and having a 24 mile commute it's hard to avoid being late at least once a year. I try to plan for traffic when it's snowing but there isn't much you can do when the freeway is stopped and the side roads have a foot of snow.
I am never late. I like to be there at least 15-20 minutes early. That way I can get my ice water, turn on my computer and get up my many, many programs.
One of the last times I was late was about 4 yrs ago when I got into a minor fender bender on the way to work. It was not my fault, it was the POLICE CRUISERS FAULT!!!!
He decided he wanted to go the other direction and I was in the turn lane. He turned right into me and dented my fender with his tire. I got a check from my insurance company less the deductible. About a year later, I got the deductible back. Never did get the dented fender fixed. I used the money for bills.