If a correctly powered drive is not spinning i.e. it is silent, it can be an indication of a problem with the hard drive Printed Circuit Board (PCB), Burn or Broken PCB
A not initialized error is a signal of a fundamental communication error. Usually an attempt to initialize a hardware failed drive will result in a low level I/O error
As with any mechanical moving parts, the friction in movement creates heat. A physical problem may therefore present as an abnormally hot condition in the drive.
A serious mechanical error is an abnormal loud clicking or a grinding noise. Continued use puts the platters containing the data at risk of permanent and irreversible damage.
Blue Screen (BSoD) , No Operating System Found, Drive Won't Mount, Shock (dropping the Laptop or PC), Bad Parts in the Manufacturing Process ,Electrical Failure / Surge etc.
A failing hard drive can present with an abnormal ticking noise while the disk is reading data. This shows disk has bad sectors due to multiple read attempts.