Which Lean tool is described as a mistake-proofing technique?

Poka-yoke is the correct answer because it specifically refers to techniques and mechanisms designed to prevent errors or defects in the production process. The term "poka-yoke" translates to "mistake-proofing" in Japanese, indicating its core function: to design processes in such a way that mistakes are impossible or immediately detectable. This approach can significantly reduce variability and improve quality by ensuring that errors are identified quickly and corrective actions can be taken.

For instance, in manufacturing, a poka-yoke device might be a fixture that only allows parts to be inserted in the correct orientation, thus avoiding assembly errors. By incorporating these mistake-proofing techniques, organizations can enhance efficiency and minimize waste, which aligns with the overall goals of Lean principles.

In contrast, Kaizen is a philosophy that emphasizes continuous improvement, Kanban is a scheduling system for lean and just-in-time production, and 5S is a workplace organization method. While all these tools contribute to improving processes and reducing waste, they do not directly focus on the mistake-proofing aspect in the same way that poka-yoke does.