Why won't my PS3 read discs a day after a factory reset?

Hi,

I have had a PS3 in the shed for 3-4 years now and my friend wanted one so I gave him it. I reset it since there were already accounts on but the problem is that the next day the PlayStation didn't read any discs. I reset it again that day with a backup I stored (the discs were working fine that time) and it worked again but the next day it had the same problem. Is it a corrupted piece of the hard drive?

Thanks