How to Improve Software Quality: Lessons from Toyota's Debacle

Recap of lessons learned

So, let's recap the three key lessons about software quality that Toyota's woes can teach us as IT professionals:

Lesson No. 1: Testing is a necessary but insufficient part of quality management.

You cannot exhaustively test complex, real-world systems—from cars to data centers—so testing should be part of a much larger process for quality assurance.

Lesson No. 2: Even little mistakes in software can have big consequences, so test software at all levels, from individual units to system integration.

Complex systems can exhibit unpredictable and, in some cases, catastrophic failures that are not proportional to the size of the defect. So, many different types of testing should be employed to try to expose any defects.

Lesson No. 3: When complex systems are built from many subsystems, with some of the subsystems being produced by vendors, risks can go up and accountability can go down.

So be sure everything, including systems you buy from vendors, works with customers. Understand, measure and manage the quality assurance process for all systems from end to end.

If you're wondering how to apply these lessons, check out my previous Knowledge Center articles, How to Build Quality Applications and How to Achieve Greater Application Interoperability in Your Data Center.

Rex Black is President of RBCS. Rex is also the immediate past president of the International Software Testing Qualifications Board and the American Software Testing Qualifications Board. Rex has published six books, which have sold over 50,000 copies, including Japanese, Chinese, Indian, Hebrew and Russian editions. Rex has written over thirty articles, presented hundreds of papers, workshops and seminars, and given over fifty speeches at conferences and events around the world. Rex may be reached at rex_black@rbcs-us.com.