Why macOS Keeps Warning That Your Disk Was Not Ejected Properly
"Disk Not Ejected Properly": What It Means

I explain why macOS frequently warns that a disk was not ejected properly, even when you didn't physically disconnect it. The issue often stems from the storage device's firmware rebooting, causing the kernel to abruptly remove the device from IOKit before a graceful unmount can occur. Understanding the difference between unmounting a volume and truly ejecting the hardware helps clarify these frustrating alerts.
When you 'eject' a volume in the Finder, that's not actually ejecting anything, it's only unmounting a volume.
- recursivedoubts
I’m surprised apple hasn’t solved this in some way. Seems like the apple is at would be to make removing the drive just work.
- jonhohle
Shameless self promotion - if you plug your notebook computer into external disks often and don’t enjoy finding them to eject every time you undock, DriveLight[0] gives you a global shortcut to eject (or just unmount) all your disks at once. You get a menu bar extra to show disk activity, too!
- gerdesj
Replace the word "ejected" with "removed" as appropriate and the error becomes apparent.
No one "ejects" an external hard disc, you remove or disconnect it. You do eject a CD or a DVD.
Eject is a forceful removal ... if my memory is not totally shagged - iacto (Latin - I throw) or similar.
To be fair I have seen a few ejections or the aftermath of discs (hard/floppy/CD/DVD) and not considered them ... a disconnect event 8)
I suggest Apple go back to school and dispense with the lazy error reporting.