I would disagree. I would assume there's a lot of people who plan their meetings and their lives (outside of connections) based on arrival time. If you're late half the time, that to me is not quite acceptable. Not that I'm asking for or would ever expect a 100%, but still.

It's like being okay your food being good only 50% of the time at a restaurant you go to. It's just not good enough (for me, anyway.)