I have seen a few guys with sore fingers, so I either put the car back onthe starter box with the switch off so the stationary starter wheel stops it, or I use the toe of my boot,
I have seen a guy panic with a run away and stick his finger on to the flywheel, it went down to the bone pretty quickly. poor bloke was in total agony. I stopped it with my boot against the exhaust before administering first aid. That finger was pretty ugly to look at