Why do some Kidde smart detectors have lower Amazon ratings than the non-smart ones?

The hardwired smart variant in particular sits around 3.5 stars, and r/Ring threads detail real headaches: each detector registers as its own device in the Ring app, so an alarm can produce a flood of duplicate notifications, and some users report setup difficulties. The non-smart Kidde alarms get higher ratings largely because there's less to go wrong.