Macbook Pro 13 (2012) refusing to have High Sierra installed on it

[Shed209]

I have a 2012 Macbook Pro 13 (non retina) that had El Capitan installed on it, but on which I'm trying to install High Sierra from a bootable USB drive. I was looking to do a clean install so I erased the hard drive and selected APFS in Disk Utility, then went back and directed the machine to install High Sierra from the USB drive. It appeared to be working fine until the machine restarted, at which point it was only able to pick up the USB drive to boot from. I tried reformatting and installing again, but the result is the same - I cannot get the High Sierra install to take on the hard drive. I know the USB installer is fine because I used it on another machine. Does anyone know what might be going wrong here?

 

[DeltaMac]

Format the hard drive again as Mac OS Extended (Journaled), NOT APFS.
The High Sierra installer will choose what to do with the drive format during the install. You don't need to do anything, other than erase the hard drive, and, in fact, only an SSD will be converted to APFS. A spinning hard drive will continue with the Mac OS Extended (Journaled) and your system will be fine with that. Slow, of course, but that's the norm now, if you don't want to upgrade to an SSD.
(I tried to force an APFS format with a hard drive. It doesn't work. It's just not supported.)