Self driving cars is s hard problem. Not least due to their reception and popular opinions against them. There is a lot of discussion and debating how safe or competent and adaptable they need to be to be generally accepted.
Of course they will fail occasionally. Of course there will be situations they can't handle. And of course humans can handle some of those situations better. But how many times humans fail in those same situations. Not to mention the different situations where the software outperforms our wetware. It's not 1:1 comparison of situations and how each handle those. Both options have their strengths and weaknesses.
When the car fails there could be software bug, device malfunction or any other technical reason. When humans fail they are tires, drunk or distracted among other things. Those things can't be fixed with an update. They haven't been fixed after over a century of cars driving reclesly on the streets depending on human judgement of their capability to handle the situation. We are terrible at making those calls.
Computers simple deem some situations too hard for them to handle and refuse to execute under those conditions. And if computer thinks it can't drive through bad weather maybe we shouldn't either.