It really depends upon the business with respect to what is an acceptable response time.
In the QS-9000 Semi-Conductor Supplement (as I remember) gave 24 hour containment which included tracking all shipped parts, etc. I think the first response had to be within 12 hours. It might have been 24-48. I forget now.
But my point is only to say it depends upon the business. Automotive will hold your feet to the fire, particularly if it's safety related or in some other way 'critical'. If you get a complaint from a customer via the 'Cracker Jack' people that one of the toy dolls you make for them to put into their boxes "...wasn't whole..." (mold didn't completely fill out or something) your response time will be different.
I can't speak for the medical device industry, but I betcha you don't get 10 days (which is generally accepted as 10 'working' days) in which to respond to a customer complaint.
That said, 2 weeks has been out there for a long time in many companies but I don't know where it 'started' or anything like that.
A Search is a terrible thing to waste!
One Test is Worth 1000 Expert Opinions - The plural of anecdote is not data - Correlation does not imply Causation
We can't solve problems by using the same kind of thinking we used when we created them. - Unknown