A lot of the other responses say something along the lines of "of course people have more incentive not to mess up, they care about their own lives more than corporations care about getting sued" and sure, that's true in general, but:

- people try to wingsuit through narrow obstacles and miss

- people try to build their own planes and helicopters and die

- people try to build submersible vehicles to go see the titanic and, uh, don't have a 100% success rate

- people try to build steam-powered rockets and die

"It's their life, they won't fuck it up" doesn't exactly cover a lot of behaviors.

I'd argue home-rolling your own medical device firmware is closer to daredevil/"hold my beer" behavior than normal.