I didn't want one either. So much so that when my wife surprised me with an Apple watch for Christmas last year, I could hardly hide my disappointment. Thinking "I really didn't *want* one of these"...
But having used a smart watch for a while now, I absolutely love it. Why?
1. The haptic feedback. I run my phone on silent 24/7, which meant that I was constantly having to double-check that I didn't miss a message while walking around. There's no missing or mistaking the prominent tap from the watch so this problem is solved. No more missed messages and no more randomly checking my phone.
2. The weather. I wouldn't have predicted this one, but having the current weather conditions plus the day's high/low temps on the watch face is super useful. I probably look at my watch for the weather conditions almost as often as I look at it for the time.
3. The general freedom of not needing my phone in my hand. In lots of small ways throughout the day, a well-functioning smart watch is another one of those "living in the future" joys. Sending messages by voice without even pulling out your phone, pausing/resuming podcasts while mowing the lawn, getting haptic navigation directions while having an uninterrupted conversation... a good smart watch is clearly a step forward.
As a former skeptic turned believer, it's a shame to see so many people dumping on these devices without having the chance to really see what they offer.