Why do over-the-range microwaves get such mixed reviews?

Reliability is the dominant complaint. r/Appliances threads repeatedly warn that many OTR units share components and suffer handle and door-switch failures within a few years, and high-trust community posts in r/HomeImprovement echo short lifespans. consumerreports.org also rated at least one Black+Decker OTR model as only mediocre on heat evenness. Buyers prioritizing venting and built-in looks accept these tradeoffs.