Android updates are always an uncertain process. A new version with new features is announced by Google, then the source is released sometime later, and then the wait begins for it to roll out to devices. Depending on your device, that wait could be fairly short or exceptionally long. If you have a Nexus device, chances are you'll be toward the front of the line (though even some Nexus devices have still experienced delays on the order of months for some updates). If not, you’re at the mercy of your phone’s manufacturer for when the update comes. Some manufacturers have been better than others at getting updates out quickly. When I bought my Motorola Moto X (2013), Motorola did an excellent job with the Kit Kat update, pushing out the update to some of their Moto X variants before even some older Nexus phones got the update. Unfortunately, with the Lollipop update, things went a bit differently.
By the time Lollipop arrived, Motorola had a new Moto X around, the 2014, 2nd Gen Moto X. Motorola still got an update out quickly, but only for their new 2014 flagship. The now older 2013 device is (at the time of writing this) still waiting for Lollipop. There are several reasons for this. First, Lollipop had its share of bugs, some pretty serious, that Motorola invested time in fixing. Second, the lower-powered, custom chipset that Motorola used in the 2013 Moto X needed more care in bringing up to date. Third, Motorola has a lot more devices to manage and update now than back when Kit Kat came out (two generations each of Moto X, G, and E, several Verizon Droid variants, and the Nexus 6).
There have been varied responses to this delay in updating the 2013 Moto X to Lollipop. Of course, you have some who respond impatiently, demanding to know when the update is coming. But on the other end, you have some who argued (often in response to the impatient ones) that Kit Kat was running well, Lollipop has issues and does not bring a lot of new features, and Motorola should take their time and do it right. While I don't agree with the demanding and impatient crowd (I write software for a living too and know it takes time to get right), I don't find myself completely agreeing with the other group either. There are a number of features and reasons why I'm ready for Lollipop on my phone and figured I would outline them here.
1. Kit Kat is not running "just fine" for me. It's not terrible, but not great either. Performance sometimes is sluggish and battery life has gotten to be downright abysmal. I have to charge my phone at least once during the day, and that's even if I don't use it much. I've never gotten the amazing 24hr battery life that some have with the Moto X, and it has just gotten worse over time. I am planning to factory reset my phone to see if that will help, but I wanted to wait until after the Lollipop upgrade.
2. Lollipop task switcher. It can get crowded after a while of use, but the task switcher is generally more fluid in Lollipop. Kit Kat also has a nasty bug where sometimes there appear to be two separate task lists and sometimes you don't get the right one, which makes it kinda useless when I wanted to quickly switch to another app.
3. Heads up notifications, especially for phone calls. I cannot stand the way pre-Lollipop handles if you get a call when using your phone. All of a sudden you get whisked away to the phone app automatically. No warning, just bam. If you happen to be tapping the screen, you just might answer or reject the call accidentally (this has happened to me). Lollipop fixes this by presenting a heads up notification that someone is calling when your screen is on.
4. Hangouts notifications are slightly broken in Kit Kat now. Something changed when Lollipop came out and now the notification only shows the last message received even if you have received multiple messages since checking it. On Lollipop my Nexus 7, the notification can still be expanded to show most of the messages you haven't seen yet. This is somewhat mitigated by my Moto 360 smartwatch which lets me view Hangout history from a notification, but sometimes it still would be nice to have on my phone. Edit: It seems this is a phone vs. tablet thing and not a Kit Kat vs. Lollipop issue. Oh well.
5. Smart Lock has improvements over Motorola's Trusted Devices (aka, I miss the lock screen!). Motorola added a feature to the Moto X that keeps the device unlocked when connected to a Bluetooth device like a smart watch. This is perfect for me as I can have a pattern lock on my phone without having to constantly unlock it. Google liked the idea so much, they built it into Lollipop. Problem is, on the Moto X pre-Lollipop, "device unlocked" means there is no lockscreen at all. Pressing the power button takes you right into the phone when connected to a trusted device. A lock screen isn't necessary, but there are little things I have missed without it (like lockscreen media controls).
6. Smart Lock works with my Chromebook. Smart Lock can do more than just keep your Android device unlocked. It can also work to let your phone serve as a “key” to sign into a Chromebook. But this only works with phones, so I can’t use my Nexus 7 tablet (which has had Lollipop for a while now).
7. Improved default app selection and share menus. The default app picker and share menus are refined in Lollipop. Both use dynamic ordering based on which apps you tend to use. Especially for sharing this makes it a lot easier than scrolling down in the alphabetical list of apps to the same place every time.
Those are probably the main things for me. Also, not a stock Lollipop feature, but Motorola has promised that the Moto X 2013 would get custom launch phrase support (which the 2014 edition launched with) alongside the Lollipop update, which should be cool.