Naturally people who don't like EVs are going to cherry-pick these problems, but the mixed results suggest to me that it's down to a deficiency in the design and testing process at some companies. I had a 2009 Prius where the rubber pad on the metal hatchback handle melted, fell off, and left a thick streak of rubber adhered to my license plate. It was a known issue in that model of Prius and affected a lot of people in the southwestern US. Was it a great engineering challenge to create a handle that could handle such heat? Did they consciously decide to sell something that would fail in an ugly and embarrassing way right below their brand logo? I doubt it; I suspect it was a new design that they failed to test rigorously enough.