Mounting/unmounting external drives: how often daily?

Mounting and unmounting external HDDs or SSDs multiple times per day is completely normal and not a meaningful source of wear. The physical wear on modern drives comes from read/write activity and power-on hours, not from the mount/unmount process itself. Having to click twice to eject toward the end of the year is usually a software or process issue, not hardware degradation.

Running Disk Utility’s First Aid is a good idea and can help if there’s a minor filesystem issue. More often, the double-eject behavior happens because an app, background process, or indexing service still has a file open. It’s not harmful and doesn’t indicate drive failure.

If you want to get a more accurate picture of your drives' health, I suggest you consider using DriveDX.

There’s no need to keep drives constantly connected to “protect” them. My general practice is exactly what you’re doing: connect drives only when needed, eject properly, and replace working drives on a predictable lifecycle.

No, it does not.