I always thought...Apple watch was a solution looking for a problem that doesn't exist.
You can make toast easily in a pan or an in an oven. A toaster then, is an answer to a problem that doesn't exist.
Why does everything have to be the only possible answer to a problem? The Apple Watch is not the ultimate answer to any one problem - but it is more convenient for a lot of things. It's been really handy for dismissing calls in meetings because I can quickly glance to see if I need to take it, and cover the watch if I want to dismiss it so my phone stays in my pocket. It means my phone is not left on tables as much and is less likely to be forgotten...
It also is handy around the house, I don't have to have my phone with me to see I've got a text message or receive a call. Would I use the watch normally for a phone call? No but in that one case, it's quite handy.
It also does make for a really great fitness device. After all it is fully programmable so you have custom apps for any purpose that you can quickly glance at. Again the phone would serve also but the watch is just much handier.
It also means that I am less tied to a particular form factor of phone. I like to run so if I were just using my phone for tracking I'd be inclined to get a smaller phone so I could strap it on my arm... but since I have the Apple Watch I have the larger size of phone than I might otherwise.
Now, if the device was truly stand alone, that's one thing
The airily named "series 2" includes GPS so you can indeed do some things (like record runs) without a phone. That is a natural evolution but for the moment I'm a lot happier with a watch that easily lasts a 16-20 hour day than I would be with a cell connection I almost never use.
Also of course, around the house all of the Apple Watches are connected via WiFi and so do not need the phone on your person...