Slowness of the system that increase with time since last reinstallation of the OS, dll conflicts (you also have a Wikipedia page https://en.m.wikipedia.org/wiki/DLL_Hell), corrupted registry, conflicting drivers, configurations, libraries.

I am not saying anything controversial, it is one among the main complaints about windows, together with worse resource management and less general stability.

That's the reason you find windows for accountants, but no one uses windows for complex systems that have to be stable, reliable and maintainable.

Many casual users live with these issues, many move to mac, few move to linux