Never. Whoever leaves the most wins. I always have a project in a bunch of bags, all the things I will need and ready to go, so many hours waiting everywhere, the only place I have not knitted is in the grocery store, I read about some people afraid of knitting in the car, they might get a knitting needle where they don't want, and that is true, a friend of mine liked to knit while driving ,at every light etc, one day she had to brake fast and she had a needle in her nose, after that she at least stopped. lolol I knit in the car but hubby drives.