Apropos, the Wikipedia article (https://en.wikipedia.org/wiki/Thrust_reversal https://en.wikipedia.org/wiki/Thrust_reversal) mentions number of events where an

Apropos, the Wikipedia article (https://en.wikipedia.org/wiki/Thrust_reversal https://en.wikipedia.org/wiki/Thrust_reversal) mentions number of events where an engine reverser was deployed in flight, one involving a 767 which resulted in the loss of the aircraft. That counts as a pretty serious thing to avoid :-).