This. It literally is 100x more intuitive, runs better and more efficiently. App selection aside and grading the OS on its own, Windows Mobile is literally the best mobile OS of the big three.
More intuitive is entirely subjective. They basically copied Android with the new Action Center, because notifications were horrid on Windows mobile. All the 8.1 update is really doing is putting Windows Mobile back on a near level playing field (Windows Mobile is more intuitive in certain aspects, but lacks a lot of the customization you get with Android) with Android. 8.1 compares really well to KitKat, but it's also not due for a few months, and Google I/O is fast approaching.
There is no way for the user to control multitasking at a fine grain level with Windows Mobile. Mail, calendar, and social media will sync in the background, but many apps won't, and it's completely aggravating. Then you have the fact that here are only two distinct places you can organize tiles; the home screen and app screen. If you use a lot of apps, it leaves you with an endless string of them to have to sort through. Sure, you can search alphabetically, but being able to separate them with folders is a much needed feature.
I like the speed and compatibility of Internet Explorer, but the lack of synced bookmarks is completely archaic. In fact, there are no folders for favorites and the lack of an organizing ability for apps leaves a huge, long and unmanageable list of links.
WP8 also doesn't have the capability of something like Spotlight Search from iOS and it's greatly needed. Yet again, not having app folders compounds the problem when you want to search for installed apps. Contacts are a pain in the ass, because it takes three clicks to search on a contact, as you need to go into People, find "all" people, press magnifying glass, THEN type in the person's name. The annoying part is that one of three dedicated bezel buttons is search, but it's just a fucking Bing search. They really need to change that to a phone search.
Lastly, Nokia Drive. I realize it's in "beta", but it definitely fucking shows. Most of the time GPS gets stuck for about 10 seconds before it'll tell me where I am. I realize that's somewhat of a "first world problems" gripe, but it feels like forever when you're trying to find out where you are or how to get some place. About 25% of the time when I do turn-by-turn directions, the phone gets confused and won't do turn-by-turn or
anynavigation. It just sits there, confused. Hell, for a long period of time the app didn't even call out street names. It just used to spit out generics like, "turn right in one mile". When in a larger city where exits are often on top of each other, it was frustrating as all hell and extremely easy to get lost. Thankfully, they finally added a voice which will spit out street names, but the older voices still just give generic directions.
With that said, Windows Mobile is definitely the most stable phone OS I've ever used. The only "crashing" issues I've ever had were with the bluetooth, but it was a very rare bug that involved a specific charger being plugged in at the same time I hung up a call on a particular bluetooth headset.