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Nearly 500 smartphone brands have left the market since 2017
(www.techspot.com)
This is a most excellent place for technology news and articles.
The only LG phone I ever had, it just randomly decided to not boot one day. Apparently it was a common issue, and they were not giving any refunds, at least when I asked. I swore off of LG then, and I wouldn't be surprised if many other people did as well.
I think the phone was the LG G4: https://en.m.wikipedia.org/wiki/LG_smartphone_bootloop_issues