The biggest fault of Windows Vista in my opinion was Microsoft made one too many compromise. There were machines that came with Windows Vista pre-installed that should have never gotten Windows Vista. My roommate in college had a Compaq machine on which the screen completely blanked for over three minutes at a time as it tried to display the user access control overlay. Of course, over three minutes later the screen would turn on as if nothing had gone wrong at all. iirc it was something about the processor/integrated graphics being too weak for Windows Display Driver Model. 
I think Microsoft is making a similar mistake today by allowing OEMs to ship Windows 10 on new machines with anything less than a SATA SSD (mechanical hard disks or eMMC).
 https://en.wikipedia.org/wiki/Windows_Display_Driver_Model#:.... Off-topic but if the url looks weird it is because it is a Chrome only thing: more at https://wicg.github.io/scroll-to-text-fragment/