> If that was compelling, we would still wear wrist watches to tell the time with. We don't
There's more "we" out there than just "you." I wear a $30 digital watch because it's indestructible, compact, accurate, and its battery lasts forever. Carrying a delicate, bulky, non-waterproof phone I needed to charge every day would suck by comparison. Try running, hiking, or doing anything outdoors with a phone, and you'll soon end up with a dead battery or a dead device.
That's not to say that I find "smart" watches compelling. The phone tethering and need to recharge every night make them useless to me. Once they can go a week on a charge and do much more than a normal watch, they may be useful. (Today's GPS watches come close.)
And anything more information intensive than the time is going to be even harder to access on a watch.
And we still have to keep our phones around anyway - the watch is just a conduit to them.