The main problem with Apple Watch is two parts:
- It's not as intuitive as an iPhone
- It's a lot slower than an iPhone
It's meant to be an iPhone accessory—which is why the above points matter so much. It's not difficult to use, but there is more friction because things are less obvious. I still get a little mixed up every now and then and I'm a fairly tech-savvy person. Some things just work amazingly well, and other things are fairly abstract.
The biggest problem, however, is that it's partially meant to be an accessory that lets you quickly check things that are on your iPhone. But when I open many Watch apps, they're extremely slow to respond and sometimes just spins for a minute and crash. That definitely needs to be fixed and I think Apple's solution in Watch OS 2 will only help partially. The logic will run on the watch, but I think many of the resources still need to load from the phone such as interactions with the UI. Right now even Apple's Weather app can be extremely slow. Some of my apps have gotten updates that make them more stable, so maybe part of the blame is on developers. But this is my biggest complaint.
Other than these issues, I really do like my Apple Watch. I can see myself getting another one in a few years. It has helped me become more healthy. However I don't recommend it to people unless they really have money to blow because most people don't need this thing…yet. Most fitness freaks can get by on a fitness band. I think in a few years it will be more useful for a person's everyday life—just like most people didn't need smartphones at first. I wouldn't have gotten one myself without the cash incentive my work was offering for fitness tracking.
Unlike the smartphone boom, Apple is here at the start of smart wearable devices. Usually Apple jumps on board well after the fact (aside from the personal computing revolution), so this is fairly early in the game for them. If anything that makes their entrance unprecedented and it will be interesting to see how things shake out. I think if Steve were around he would bide his time for a couple more years so that he could identify the exact problems and address them with one amazing device. Instead Apple released something that is better than the competition but not significantly so. They tipped their hand a little early. Eventually competitors have caught up to the iPhone—but the key is that it took them a long time because the iPhone was so ahead of everything else. The Watch isn't, and it will be easy for them to copy it. A big key to Apple's success is secretly coming up with all these amazing features while everyone else in the industry is asleep at the wheel with little innovation. Apple then comes in and disrupts everything with a fully realized, complete design thought. The Apple Watch is not a complete design thought. It's really good, but it's not at that level. Nobody will look back at the launch and compare it to the iPhone. They'll look back on it as a successful device that had a very long run. But it's not at that extreme, game changer level—and sometimes that's ok.
TL;DR: Using an Apple Watch has some friction, especially with app responsiveness. It's a really great device but not a game changer like the iPhone. Most people don't yet need one. It's an accessory and not significantly better than the competition, so Apple will need to work hard to keep ahead.