Most important feature of a wearable

Is for you to want to wear it!

Maybe the Apple Watch won't last you all day but if you won't use it because is ugly what's the difference?

At least Apple made a bunch to models, with different sizes, materials, bracelets to reach the style of each individual person. 

For those asking for the "why" of this product:

..you can only connect the dots looking backwards..
— Steve Jobs