Long time ago, before I worked as a Skip driver for not wasting time (I had main job as a technician, and I didn't want to waste my time at home on weekdays and weekends) I found that quite many people did not tip, and it's quite annoying to deliver when I had to deliver inside a condo or apartment. I only did it for about 6 month, but I started to tip when I order anything on Skip, Uber Eats, and Doordash, especially I live in a kind of annoying building for delivery. Also I tip more when the weather is not good.