How about not testing it on the unpaid public in incremental patches like this age of software "engineering" has decided it was a good idea to do?
It is more an issue of how sophisticated these vehicles should be before they're let loose on public roads. At some stage they have to be allowed onto public roads or they'd literally never make it into production.
If they're not willing to dogfood their own potential murder machines then why should the public trust them on the public roads?