It's not as if the person who says "I could care less" when he intended to communicate
the message that he "could not care less" is "wrong" because he has violated some linguistic rule.
He shows a poor understanding of competent reasoning.
That makes him look bad.
If I want staff who will make mistakes in logic on-the-job,
then I 'll hire him !
It's simply because he is uttering the opposite of what he intends.
He isn't listening to himself adequately.
He is just mentally sloppy
, and it leaks out his mouth.
If I had a surgeon who represented himself that way,
I 'd find someone more trustworthy to do his job.
When I was hiring personnel (professional and support staff)
for my law firm, in another century, I judged them by how well
thay spoke, among other criteria. I wanted staff who were
meticulously precise in their mental operations.
There was an ABUNDANT pool of labor available.
I took the best of the best candidates and we paid them decent salaries.