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And so we had a lot of great ideas when we started [the Mac]. But what I've always felt that a team of people doing something they really believe in is like is like when I was a young kid there was a widowed man that lived up the street. He was in his eighties. He was a little scary looking. And I got to know him a little bit. I think he may have paid me to mow his lawn or something.
And one day he said to me, "come on into my garage I want to show you something." And he pulled out this dusty old rock tumbler. It was a motor and a coffee can and a little band between them. And he said, "come on with me." We went out into the back and we got just some rocks. Some regular old ugly rocks. And we put them in the can with a little bit of liquid and little bit of grit powder, and we closed the can up and he turned this motor on and he said, "come back tomorrow."
And this can was making a racket as the stones went around.
And I came back the next day, and we opened the can. And we took out these amazingly beautiful polished rocks. The same common stones that had gone in, through rubbing against each other like this (clapping his hands), creating a little bit of friction, creating a little bit of noise, had come out these beautiful polished rocks.
That's always been in my mind my metaphor for a team working really hard on something they're passionate about. It's that through the team, through that group of incredibly talented people bumping up against each other, having arguments, having fights sometimes, making some noise, and working together they polish each other and they polish the ideas, and what comes out are these really beautiful stones. (Source