Honestly, it was probably a freak accident. You got the rare one that was faulty. As the others have said, modern CPUs are pretty hard to kill. The processors are made by Intel or AMD, which have way tougher quality standards than Dell. 
My wife and I have had 4 Dell PCs, usually getting a new PC every 5 years or so.  Each one lasted the entire time without any issues.  My recent 8930 was purchased in June 2019 and the processor died recently.  Since my warranty ended last June, I had to pay to get it fixed.  I'm disappointed that the processor only lasted a year and 10 months.  Has anyone else had issues with a processor in the recent 8930 PCs? Thanks.....Tom
XPS 8930, Processor died