A hard drive does not die in silence: first it starts to "think" for a couple of seconds longer, then it forgets folders, and in the end it puts on a farewell concert of clicking. All of this is the language of hardware asking for help.
There are three signals that cannot be ignored: files open with a delay, the system freezes when copying, and strange sounds appear at startup. This is not "old-age lag", this is the HDD chewing through its last sectors before becoming a useless piece of metal. The irony is that backups at this point are only made by those who have already lost everything once.
Our technician in red-and-gold armour believes that a drive should retire on its own terms — after transferring data to a fast SSD. We know how to pull your gigabytes out of even a nearly dead drive. And how to breathe so much speed into an old iMac that it will surprise itself.