While I truly feel at the moment that the whole smartwatch thing is a gimmick and I couldn't care less whether smartwatches totally fail to catch on or not, I can't believe how much people are bemoaning the fact that they need to be charged every night (or at least every other night).
It's not so far back in the past that mechanical wristwatches needed to be wound up every night else they'd be useless the following day either.