extended visit in the US not planning to return to Canada

So what would happen if my friend visits the US from Canada and never plans to return? If he doesn't plan to ever go back then they wouldn't check to see how long he has been visiting, correct?

Why does it take so long to get a green card on your own to come to the US? Up to 7 years!

Is your "friend" visiting an immediate family member or U.S. spouse? If it is a spouse then it would be about 6 months to a year. If it is an immediate family member, you are looking at more than 7 years,,,more like 10 +

And if said "friend" never plans to return to Canada but does however visit another international destination, he/she would have a difficult time returning to the U.S. unless there is good reason. I would tell this "friend" to sit tight in Canada until he/she knows what their clear intent is for being in the U.S.