iMac white screen with file folder icon i.e. fails to fully boot

The iMac has started going to a white screen with the file folder icon that has a question mark.

Following steps have been performed:

P-Ram has been reset

First Aid run on the HD 2 times, no errors found

Erased HD twice

Re-installed MacOS

At the end of the install the message to restart the machine appears but upon restart the white screen appears again.

No solution has been found as to why the failure occurs since all of the first aid and logs check out in working order.