Linux

It seems like a big company's problem. They have a well-paid design\marketing department that can do whatever they want to create the best-selling interface for the new version of Windows, but before it's released, no one tested it yet for anything but bugs, and who'd argue with a flock of top designers anyway? Add here the board of directors who are here to sell them ideas and who won't use it either – I'm sure they applauded to the idea of unifying mobile and desktop experience with WinPhone&Win8, but especially Tablet-Laptop transformers they saw as the future. It sounds great on the paper, right? At that time it could've even sounded obvious for their business. And so it happened like it did.

Linux counters it by constant feedback and competition between easily switchable DEs, users being prepared even to jump distros; Apple has a fetish for style and experience (that's a half of their pricetag), they build their business model about looking and feel nice, so you'd build an ecosystem of their products, you can't even see error windows here and their garden is gated af; and ChromeOS\Android aren't shy of looking what others do (like iPhone's design findings) and conservatively taking what works, also having tons of vendor-created restyles\forks on their own platform as a testing ground for new ideas to make them then a standard. MS lack all of it, and their creative process is guided by external interests and ideals, it's just an afterthought. And as they have their stable market share, they probably won't even care. It took whole internet's screams to return their traditional start menu in win8.1, then w10.

That'd probably stay the same until their new CEO would happen to be an art college graduate - like the current one pushed for accessebility and building special controllers because she has a child with a disability. A top-down signal. I won't bet on it anytime soon.