For all things Windows.
Fucking thing just locks up my system while it tries to load for 5 min then it does load but then is completely frozen for another 5 min then you click to exit and its another 5 min before it goes away. I can't just turn on my computer and play a game anymore I have to wait for windows to pull its head out of its ass and stop hogging system resources for me to actually use the god damn machine.
If MS wants people to use its operating system it needs to get the fuck out of the way of the user operating the system. So much god damn useless feature bloat and background "services" tying up cpu and disk write cycles makes for a frustrating user experience.