From what I can tell, outside of the extremely tech-centric realms of society, smartwatches like pebble will not find any success.
Watches are both a utility device, as well as a fashion accessory. For most people, it has become mostly a fashion accessory first, a utility device second. Pebbles really don't look fashionable to most people, both on style, and on brand perception. People will put up with a bit of questionable styling if the brand signaling is good enough, but the reality is, the vast majority of people will not recognize a pebble, and instead will just see a not very stylish device on your wrist. As a fashion accessory, the pebble fails incredibly, and to build a scalable standalone watch company around watches which don't pass as fashion accessories is just a recipe for failure. Even the pebble steel isn't good enough.
So while people claim that the idea is good, the product is good, my opinion is that the product fails to do what most consumers actually need it to do. Sure, it had a big presence on paper because it was one of the first to bring the concept of smart watches to many people on kickstarter, but like that cooler which had a boom box, charging ports, and a blender, sometimes what gets people excited when they first see an idea online, doesn't actually translate to a product that fits their actual needs.
I think this may be why almost all the smartwatches are transitioning to fitness tracking as the main feature - the idea of what a fitness tracker is, looks like, and signals is very different from a smartwatch. Additionally, it's helpful that fitness tracking is actually a utility that generally can't be done well in other devices (smartphones).