When I conduct training sessions, I often refer to the following
quote, which I heard years ago, but cannot seem to find attribution.

"While touring a Ford plant, an executive stopped to ask an assembly
worker what he does for a living.  He pointed to a bolt inside the
wheel well and stated, 'I screw this bolt into place.'  Further down
the line, the same executive asked another assembly working what he
does for a living and he said, 'I build Fords.'"

I would love to know the source of this so that future uses will lead
to my being able to give attribution.

Thanks!!

I have not found a source for your quote, but it reminds me very much
of this old parable:

A man is passing by a construction site where he sees three brickmasons. 

He approaches the first worker and asks, 'What are you doing?" The man
says, "Making $25 an hour."

He asks the second man the same question, and gets the answer, "I'm laying bricks."

When he inquires the same of the third worker, the man responds, "I am
building a cathedral."

The "cathedral" story may be found in many versions all over the Web:

://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22laying+bricks%22+%22building+a+cathedral