Look it up, and sure enough that laptop won't run the OS version Apple is trying to automatically update their computer to.
Surely Apple must be able to tell that hardware that they created cannot run an OS that they created?
How is there not a class action lawsuit over this practice yet?
It isn't just a hardware-software mismatch, it also happens because you have a failing hard drive. A failing hard drive might be compensating for it's problems but then when you do an OS update it does a huge volume of writes that overwhelms the bad block table and then your machine is trashed.
Unfortunately you don't get good error messages in this situation.
You have to replace the drive and reinstall the OS in that case. I had it happen to a Windows machine circa 2009 also it happened to a 2011 Mac Mini Server that had two magnetic drives. When the drives died I put in SSDs and I have run both Windows and MacOS X since.
Also I think if the filesystem is corrupted the same thing can happen.
One of the reasons you should try to avoid running commercial OSs IMHO.