ePSA passes, SA fails HDD test

Hi,

Yesterday I run Dell SA (SupportAssist) and suddenly it showed me an hardware issue found (Critical issue). So when I clicked on fix now then it was showing this = 

We detected an issue with your hard drive. Don't worry. Your warranty has you covered. 

Solution: Replace hard drive
The moving parts in a hard drive wear out over as a result of normal use. We detected that your drive no longer meets Dell's recommended performance levels, making it vulnerable to failure and data loss.

So I connected Dell Technical support regarding the same and then they asked me to run and check the Dell built-in ePSA diagnostics test and I did that but everything was fine and it showed that all tests passed successfully! But when I checked again in SA then it was showing the same hardware issue found. So Dell is ready for the hardware replacement but I am just curious why Dell's ePSA built-in diagnostic test didn't found anything wrong?

Also I have already tried by reinstalling SA and also I have tried by resetting the BIOS to defaults but it didn't worked out.