But Welch has moved Six Sigma beyond internally focused quality control in manufacturing to customer service.
"He's done the typical Welch thing [with Six Sigma] where nothing is done half-heartedly," Tichy says. "Everything is done 150 percent."
Six Sigma has become such an integral part of the GE way that Welch calls it the "language of leadership" at GE.
"I'm confident when the Board picks the next CEO 20 years from now, the man or woman chosen will be someone with Six Sigma blood in his or her veins," Welch said at the shareowners' meeting.
Six Sigma will continue to play a role in GE's future success, but company watchers say GE's digitization efforts, started under Welch, will become increasingly important in the maintenance of its global leadership.
Welch's greatest legacy, Brokaw says, is his development of GE into a global competitor ready to compete in the new market.
"He took GE perfectly positioned into the 21st century," Brokaw says. "My heart kind of sank when I heard GE was buying NBC and I always thought of it as a home appliance manufacturer, a buyer of big products and turbines. It's now this company that does everything from capital [to] entertainment."
Working On His Swing
Looking ahead to his retirement, Welch said in the 1998 Business Week interview that while he may consider teaching an occasional business course, he will spend most of his time golfing with his second wife, Jane.
And while he says he will miss the action and energy of his job, Welch said his retirement is part of the natural order of things.
"Succession is part of the rebirth of an organization," Welch told Business Week. "I'm not going to be around. I am not going to be near the board. It's a free swing for a new team."
The working-class kid from Salem, Mass. has come pretty far. And Tichy says Welch has had some fun along the way.
"This guy is in your face. You say 'Good morning' to Jack and you better be ready for a debate," Tichy says. "It can be stressful if you can't stand up to him, but for those who play it's fun."
--Staff writer Juliet J. Chung can be reached at jchung@fas.harvard.edu.