The professor, who has a deep background in Six Sigma, maybe shouldn't be teaching about Lean. I'm not qualified to teach about Six Sigma, so I don't try telling people what Six Sigma is about.
I do know Lean pretty well.
As other posts on this blog point out, a statement like this is very incorrect... factually incorrect...
As written here:
"Six Sigma uses the DMAIC (define, measure, analyze, improve and control) method to reduce defects. Lean, derived mostly from the Toyota Production System, focuses on cycle time reduction by eliminating non-value-added steps."
The implication is that Lean doesn't help reduce defects. The implication is that Six Sigma is the only way to reduce defects. That's all untrue.
See the Toyota Production System page that explains how Lean is about improving flow AND quality. Improving flow leads to better quality. And, Lean has methods (tools like error proofing and management mindsets) that very directly improve quality.
I wish Six Sigma people would stick to teaching about Six Sigma.
Would you let a physics professor teach biology? Would you "merge" the departments into something called "Physology" or "Physics Biology?"
That's my problem with Lean Sigma... the incorrect things that get said about Lean.
I'm not against Six Sigma. I agree that Lean and Six Sigma can be complementary. But not if you think Lean doesn't address defects. Visit a Toyota plant and see...