&gt; It doesn&#x27;t really have to be perfect as long as it doesn&#x27;t fail in common scenarios.<p>i agree that it doesn&#x27;t have to be perfect, but the standard should be higher than &quot;doesn&#x27;t fail in common scenarios.&quot;  we should also expect graceful handling of many uncommon but plausible scenarios.  we expect human drivers to handle more than just common scenarios, and human drivers are pretty bad.