That day, when the CPK report came out, the whole room fell silent for three seconds
I remember a time when, to boost output, our factory introduced a new "piece-rate system." We thought more work would mean more pay, surely motivating everyone? But what happened? In less than two months, during a weekly meeting, Old Wu presented the latest CPK report, and everyone was stunned. The CPK for that critical process had plummeted from the original 1.35 to 1.08, and DPMO soared to 6210. The entire meeting room was silent for three seconds. I thought to myself, "Oh no, this is disastrous." Everyone was just focused on volume, and quality hit rock bottom.
Where Did the Problem Lie?
Simply put, the original intention of the piece-rate system was "incentive," hoping employees would do more and earn more. However, in high-precision, quality-critical industries like semiconductors, focusing solely on quantity easily leads to a "get it done, not get it done well" mentality. Think about it: when you earn an extra dollar for each wafer produced, would you spend time checking for subtle defects? Would you slow down to ensure every step is meticulously completed? Frankly, people are driven by self-interest; when the reward mechanism is tied only to output, quality will naturally be sacrificed. This fundamentally contradicts the lean production philosophy we pursue, which emphasizes "value stream" and "waste elimination," with quality as its cornerstone.
Therefore, the key is that when your incentive mechanism is tied solely to "quantity," employees will put all their energy into "doing more," rather than "doing it well."
How Was It Actually Done?
To solve this problem, we later redesigned the incentive mechanism. It's not that piece-rate systems can't exist, but they must be linked to "quality" and "efficiency."
- Quality Threshold Setting: We set a quality threshold. For example, if your defect rate is above a certain value (e.g., DPMO > 2000), even if you produced many wafers, your piece-rate bonus would be discounted or even zeroed out. Conversely, maintaining exceptionally high quality would result in additional rewards.
- Multi-Skill Certification Bonus: Employees were encouraged to learn operations at multiple stations. The more you learned and the wider the processes you could support, the more additional bonuses you received. This not only increased the production line's flexibility but also prevented everyone from rigidly sticking to their single "piecework" station.
- Team Performance Bonus: A portion of the bonus was tied to the overall team's performance, including yield, equipment utilization, and even learning curve improvements. This encouraged everyone to help each other instead of just looking out for themselves.
In other words, we needed employees to realize that simply "doing more" was useless; "doing it well" or even "doing it better" was what truly earned them money.
The Most Common Pitfalls
We also fell into quite a few traps initially. The most common was "setting the reward threshold too high." At that time, we set the DPMO quality threshold at 500, but almost no one could meet it, which instead demotivated everyone. We later realized that it's important to proceed step-by-step, starting with easily achievable goals to give everyone a "taste of success," then gradually raising the standards.
Another pitfall was "insufficient communication." When the new system was introduced, many people were confused and felt the company was "making trouble again." So we spent a lot of time explaining, showing them calculations of when they could earn more and when they would earn less, to gain their understanding and acceptance. Honestly, this was more exhausting than designing the system itself.
One Thing You Can Do Today
Re-examine your incentive mechanism and ask yourself: "Does this reward truly deliver what I want?"
Article Category: Lean Production