The Outdated Iron Triangle

When it comes to software development, what is quality? Is it the elegance of the code? Is it how well the software performs once deployed and operating at scale? Quality is all of that and more. Ultimately, quality software is defined by three simple measures. First, it works as planned. Second, it performs well within the scope of identified use cases. And third, it has a low rate of defects which means that the software produces very few, or no, errors when a user executes one of the applications use cases.

Many development organizations utilize a classic approach, such as the Iron Triangle, to influence quality. They either reduce scope, extend the delivery schedule, or throw more engineering resources at development. But none of those ultimately guarantees quality. Even if you limit the scope to a single function or use case, take an extra year to improve the efficiency of the code, and hire a hundred more developers, the quality of the finished application can still be poor.