Problem with terminal trying to create macOS sierra usb boot drive

FYI, the macOS 10.12 Sierra installer is broken when used to create a bootable macOS USB installer. Apple was informed of this issue many years ago and instead of fixing it, Apple removed it from the download links for several years, but I guess Apple forgot it was to be hidden.

The fix is extremely simple and requires changing one character within a single file within the installer package.....yes, that is too hard for Apple to do themselves. Here is the Terminal command you need to use to fix the installer prior to using Apple's command line instructions:

sudo  plutil  -replace  CFBundleShortVersionString  -string "12.6.03"  /Applications/Install\ macOS\ Sierra.app/Contents/Info.plist

FYI, here is one of the older links to show this has been an issue since at least 2021, plus it provides a bit more detailed instructions.....see post by Eau Rouge:

Trouble creating bootable disk for Sierra. - Apple Community

What you showed ending with Done is completed, yes.

Any Mac that’ll run macOS 10.12 Sierra will also run macoS 10.13 High Sierra.

macOS 10.13 has various updates and fixes that missed macOS 10.12, and includes newer network security updates.

Older systems can have difficulties making connections to newer systems with newer security requirements, if the connections from older systems are not just blocked.

Maybe the following works with macOS 10.12, if the command syntax somehow changed:

sudo "/Applications/Install macOS Sierra.app/Contents/Resources/createinstallmedia" --volume /Volumes/pleasework --applicationpath "/Applications/Install macOS Sierra.app"

Posting the actual command used and the error message shown can sometimes be helpful.

I’lm going to guess you tried to sudo the disk image (DMG) file or the PKG package. That won’t work. The DMG needs to be mounted and the PKG package unpacked, first.

Here are the Apple instructions for the download, including how to access and unpack the installer:

Once unpacked, here are the Apple instructions for creating the install media, and summarized below:

For macOS 10.12 Sierra (I’d strongly suggest using macOS 10.13 High Sierra here), use the following:

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Alternatively, using (vertical! not angled!) double quotes " syntax to avoid having to escape each of the spaces:

sudo "/Applications/Install macOS Sierra.app/Contents/Resources/createinstallmedia" --volume /Volumes/MyVolume

Again, I’d strongly suggest using macOS 10.13 High Sierra here, as that’s slightly less old and slightly less hassles than macOS 10.12 Sierra will be.

Okay, so the macOS 10.12 installer is present.

Do you have a removable media (flash) drive named “pleasework” mounted?

See “Connect a USB flash drive to your Mac“ here: Create a bootable installer for macOS - Apple Support