Alerts are my primary reason also; the only time I do any vigorous exercise I certainly won't wear a smartwatch due to the risk of damage, so that functionality isn't of much use. I don't want to wear a watch in bed or in the shower either. I'm not keen on biometric data being collected anyway so it's good that the latest version of Android Wear allows denying sensor permissions.

What would be ideal would be a smartwatch that can manage to set Google reminders without having to have Google Now turned on; that, plus the occasional text message and even more occasional use of navigation, are all I use it for other than looking at notifications.