Watch + AirPods = killer app. It just needs more storage, but that will come in time. 3-4 generations from now and you won't even need a phone anymore.
I have seen three reasons repeated over and over why people like them and it seems so minimal of reasons. like someone mentioned, no one seems to justify wanting one until they have it but then I just figure they have to justify it.
Airpods are very nice and those I can find every day usage for, exercising and the like. far more than having a watch on my wrist as I tend to sweat a lot while exercising and don't need that.
so when it does not require my phone because it is a phone, I might sign up. but by the time phones get to that size I would just slap it on my shirt like Star Trek