Jamie Crain wrote:
Yes that's correct, however you can't do this if you've already formatted the drive for APFS. The other format options are removed from the list of options. To get around this you first have to "Delete APFS volume..." from the main menu.
If you follow @P. Phillips instructions to "Show All Devices" within Disk Utility and erase the whole physical drive, then it should just work. The physical drive will usually be identified by the make & model of the drive such as "Apple SSD SM128...", or "HT54xxxx....", etc. If you try to erase an APFS volume such as "Macintosh HD", then you are correct that it may fail.
I did this and was then able to reformat as macOS journalled. I tried to reinstall macOS at which point the computer thought I was installing Lion. The install failed, and when I tried it again it correctly selected High Sierra macOS.
If you are attempting to install macOS 10.6 to 10.10, then you need to first use Disk Utility from the 10.6 to 10.10 installer to partition & format the whole physical drive by following the instructions in this article:
https://www.owcdigital.com/assets/support/support-formatting-and-migration/Mac_Formatting_6-10.pdf
Sometimes a drive can have some type of odd partition information on it which may cause macOS & Disk Utility to be unable to work correctly and would possibly require more drastic measures, but that does not seem to the case for you if the instructions in that video worked since it only advises to first remove the APFS volume.
It is unfortunate Apple makes these things so confusing and keeps changing their documentation and eliminating the old instructions & information to focus only on the new operating systems.
Just keep the information provided in this thread by all the contributors in mind if you ever have to perform a clean install again on this Mac. Each contributor has included little bits of different information which is important to know.
