You think they don't?
You think they don't?
Being responsible for some one else's safety should have a higher bar than being responsible for your own safety.
I cannot claim to have done the onboarding process myself, tried to look up online and the most I could find is that a good amount of time is spend on doing background checks. I was able to find Uber's employee onboarding information for their corporate employees and it turns out that there is indeed some training required for people who are managing your corporate property. Ironically I do not see any mandatory (ideally paid for) training provided by Uber to drivers when they are handling other human beings (passengers). And to be fair its hard to predict everything, mistakes happen unfortunately, the goal should always be to get to a better state than where we are as of today.