ALTHOUGH MCDONALD’S (MCD) has since tried everything from cafes to chicken joints, the company’s foundations (and real growth) came from Ray Kroc’s original, stunningly simple concept: a burger joint that was cheap, efficient, consistent and, most of all, fast.

And while the company already had a solid footing, Apple Computer’s (AAPL) real growth came in 1984 with the introduction of the Macintosh. Even though the machine was more expensive and less powerful than its PC rivals, the computer “for the rest of us” succeeded because of one solid premise: You could actually understand how to use it.

Today, Ford Motor (F) is a large car conglomerate of brands encompassing everything from Mazda to Mercury, Lincoln to Land Rover. But Ford became the largest car maker thanks to the Model T, a mass-produced, reliable, cheap auto with no bells, whistles or variations whatsoever. As Henry Ford supposedly said, you could have it any color so long as it’s black.

The point is that each of these magnificent enterprises succeeded by focusing on a relatively narrow goal. Get that right, and everything else usually just falls into place. (more…)