When Apple (or any company) launches a product, such as the upcoming iPhone 6, there’s always the chance that a critical flaw will be discovered by first adopters. How exactly the company handles the devices that are returned and tracks down the source of these issues has always been somewhat of a secret process.

Today, Bloomberg’s Businessweek published a profile on the “early field failure analysis,” which is responsible for taking these returned devices apart, analyzing any issues, putting together a fix, and getting it into new production devices before the problems become even more widespread.

It’s an interesting read that shows how much effort Apple puts into identifying problems that appear outside of their regular testing procedures.