January 26, 2015

Waterfall + QA


Take the product owners, product managers, and business analysts who come up with business requirements for a software product that customers might need. Take a bunch of software architects who design the blueprints of the software product. Add the designers and user experience people to sketch the look-and-feel of the software product. Software developers to construct the product. Quality assurance engineers to test the product. How does the team work together to build, test, and launch the product?

That is the software development process.



The next few blog posts will describe how software development methodologies have evolved, and with that how the role of Software Quality Assurance has changed since I started working in the industry.

Let me start with the first method that I encountered back in the mid-1990s...

The Waterfall Method


When I first started my Software Quality Assurance career as a consultant at Oracle back in 1996, the method that was most common for developing software was the waterfall method, which has been in use since the 1970s and 1980s.

With the waterfall method, the software development process was broken up into different phases: Requirements, Design, Implementation, Verification and Maintenance. If you diagrammed it, it would be described as a waterfall. During each phase of the project, artificats and deliverables such as project plans, technical specs and database design documents would cascade down to the next phase of the project.

The business analysts in the Requirements phase would draft documents detailing the requirements of the software product they would build, the purpose of the product, a software requirements specification detailing a checklist of business requirements, a high level description of the system.

This would be handed off to the software architects who in the Design phase would write the blueprints of the product. Each software component would be sketched out, the data structure of the database would be designed.

In the Implementation phase, the software developers would construct the software product.

With the Verification phase, the software testers would create test plans to describe a high level approach on how to test, and once approved, test cases detailing more on what would be tested, and once approved they would generate test scripts listing step-by-step how they would go about testing the product. Hopefully, by the time the product was ready for testing, the test plans, test cases, and test scripts would all be written.    

With the Maintenance phase, the software product would be released into the wild. The customers would use the product, and any questions, complaints, and other feedback would be gathered to help improve the next version of the product.

There were many problems Quality Assurance encountered with this method.


  • What if the reason a bug occured was because the spec or the design of the software product was unclear? As a QA Engineer, you could try to independently read through all the previous stages deliverables on your own as they were released, to try to get a feel for the purpose of the software product ... but QA wasn't actively involved until the project was almost finished. 
  • What happens if all the preceeding stages took longer than what was scoped out? It would always be easier for the time allotted for QA to be scaled back than to push back the release date. Sometimes the best you could do was tp record all bugs found, triage them, and try to get them fixed in the next iteration of the product. 
  • What if there were last minute change orders? Are the test plans, test cases, and test scripts still valid when the official validation period starts? 
  •  Development and Quality Assurance were not integrated with one another, fostering in some places that I had worked as a consultant an "Us vs Them" mentality. Some QA Managers saw the QA Engineers as a rubber stamp to okay everything the developers did. Some would claim that their job was to act as a roadblock to the developers. 


The relationship between DEV and QA shouldn't be the relationship between an Artist and an Art Critic. It should be more like a Writer and a Copyeditor, where everyone knows that they are on the same team, helping make a quality product.


-T.J. Maher
 Sr. QA Engineer
 Quincy, MA
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