A phrase used by Bubbles on the popular Canadian tv series Trailer Park Boys, used as a smart-ass reply when someone asks something to which the answer is yes.
Randy: Does it really launch? (referring to a model rocket)
Bubbles: Does it really launch?! Does the tin man have a sheet metal cock?
Originally from advertising for Ronseal woodcare products this phrase was quickly picked up by the public and turned into a general purpose phrase meaning "the name describes exactly what it is". This must be one of the most successful advertising slogans of all time. Of course Ronseal have trademarked it!
A product or process that just does what it's required to do, often used for lacklustre things that are just about good enough for a job, but nothing special.
That phone is pretty simple, but it does what it says on the tin so it'll do for now.
Someone with little technicalknowledge who gives a review of a product or service would say this phrase.
They would feel as if they are handing out good advice to people; But in reality they dont have the experience or analytical ability to give a detailed review.
John: "How is your new camera?"
Bill: "it does exactly what it says on the tin"
John has no idea whether the camera is good or not. He just knows that it takes photos.
If Bill had more technicalknowledge, he would have given more useful information.