Generally, boxed CPUs are purchased from regular retailers such as JD.COM and Yixun, or users who are completely unfamiliar with computer hardware don't know that they can buy piecework CPUs, or they are not very comfortable about buying piecework CPUs.
Another point is that the boxed CPU is generally guaranteed for 3 years, and the scattered CPU is generally guaranteed for 1 year. However, CPU is the most trouble-free accessory. There are good and bad CPU, and there is no sudden failure after normal use for a period of time. Usually, if the CPU is not overclocked, damaged or flooded, it can be used until it is completely eliminated. I haven't seen an example of sudden CPU damage under normal use.