Frequently, in spoken dialogue one hears the above phrase used as a suggestion to the listener (or sometimes more strongly, as a command):
- Why don't you give me that book?
- Why don't you go to the store and get some more milk?
- Why don't you make me a sandwich?
In these examples, the speaker is clearly not asking for the reason the listener is not doing the action in question. It's true that the listener is not actually doing the action (yet), but there is no particular reason for the inaction. The listener is simply unaware of the speaker's desires.
In the instances above, "Why don't you …" could be replaced with "Would you …" and the meaning would be the same. The latter sounds more natural to me.
What is the origin of the "Why don't you …" phrase and when did it come into use? Is this a regional usage?
Best Answer
The expression suggests a command especially when used by itself with a question mark at the end. When used as in the sentences you show it suggest more a kind of polite request (much more common ) . Both usages dates back to the beginning of the 19th century and their usage has been increasing since then especially as a polite request form.
Why don't you?
Source: McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
NgramWhy don't you
Ngram Why don't you?