As you start to scale up and formalize your manufacturing process, you’ll need to think about quality control in manufacturing. Depending on what you’re making, you may have some formal quality-control tests in place before you even start selling a product. But if you’re making something in an industry that’s not heavily regulated (say, you’re selling T-shirts on Etsy), you might not have thought about quality control in a formalized way yet.
What is quality control and why do we need it?
Let’s look at the example of Princess Capybara, who runs a cookie bakery.
We said in our discussion of manufaturing yield that she has to throw out cookies for several reasons:
- Dropped on the floor
- Burned on one side
- Not enough chocolate chips
- Crack on the top
We didn’t ask one key question, though: why does she have to throw out these cookies? In other words, why do we ever have parts we need to scrap?
Legal reasons for quality control in manufacturing
The cookies that fall on the floor probably have to be thrown out for legal reasons. If you work in a regulated industry like pharmaceuticals or food, not all quality-control decisions will be up to you. There will be laws you have to follow because you’re making something that could harm people if something goes wrong.
Marketing reasons for quality control in manufacturing
Princess Capybara throws the other cookies out because she wants satisfied customers. She wants people who buy her cookies to be delighted with the quality so they will buy more in the future, tell their friends, and write good online reviews.
She does not want customers to be unhappy with their purchase so they demand refunds, never buy again, and write bad reviews. So Princess Capybara implements quality controls in her manufacturing line to avoid selling cookies that her customers won’t like. (Specifically, those that are burned, cracked, or don’t have enough chocolate chips.)
She has to balance this, though, with the fact that not every cookie will be exactly identical due to inherent variation in the process. How does she decide exactly how dark of a bake is considered “burned”?
How does she decide how many chocolate chips are enough per cookie? And, while we’re on the subject, why is it that each cookie doesn’t end up with the same number of chocolate chips?
The answer to those questions will be the subject of a future post in this Quality Control series. For now, though, just know that quality control in manufacturing exists for two main reasons: legal requirements and customer satisfaction.
Think about your own product and about some reasons you’ve had to scrap product in the past. Do you have formal quality control tests in place? Most importantly, are there any you’ve been doing in an ad-hoc fashion that you’ll need to formalize as you scale up your process and start adding employees? Comment below!