Years ago I owned a (U.S.) 1974 Saab 99. One day while driving it, the ignition switch failed and stuck in the "start" position. 1974 was one of the few years when the ignition/seatbelt interlock was required in the U.S. As long as I was seated in the vehicle, all was well, but if I tried to get out, the car would try to start again!
Nothing untoward resulted since it was a weekday and I was able to drive to my favorite auto hospital and holler at them to come disconnect the battery.
Thankfully, it was quite easy to defeat the interlock since it had the effect of being quite a nuisance if you tried to drive it with something of any significant weight setting on the passenger seat.