I think the severity of the event is also important. A Onewheel requires power for stability (it's an inverse pendulum), and as a result does not fail-safe. An

I think the severity of the event is also important. A Onewheel requires power for stability (it's an inverse pendulum), and as a result does not fail-safe. An occasional motor failure on an e-bike would be a non-event, as it fails to a safe state. An occasional brake failure would be significant.