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I have chipped or cracked screen protectors, and currently have a tiny scratch in the screen of my phone, but I've taken care of my phones.
The one time I had to replace a broken screen on a phone, it was because Apple sold me a garbage iPhone. 12 days out of warranty (but still about 10 months left under contract) and the digitizer started dying and caused a blob 1/4 the size of the screen to go dead. They offered to let me pay half the full price for a new phone. I told them to pound sand. I bought the replacement parts and a tool kit and disassembled and reassembled my phone to the new screen.
In 14 years, I've had 6 phones and all of them survived intact.