When I started my first full-time role as a QA engineer, I thought testability was all about the code.
If the code was well-structured and the tests were well-written, everything else would fall into place, or so I believed.
But within my first year, I quickly realized that testability is about far more than just clean code.
It’s shaped by how people collaborate, how teams communicate, and how processes are designed.
A Lesson From Experience
One of the first big projects I worked on taught me this lesson the hard way.
Our team had built a new feature with solid code, good architecture, and passing unit tests. Everything looked great in theory. But as we approached the final stages, we ran into a major problem: “We couldn’t run proper end-to-end tests until right before the release.”
The reason had nothing to do with code quality. No one had prepared the necessary test data. The backend changes blocked our UI tests. The product owner hadn’t clearly explained how the feature should be validated.
In other words, our biggest obstacle wasn’t technical, it was about communication, planning, and coordination.
A Broader View of Testability
After that experience, my understanding of testability completely changed.
I stopped thinking of it as just a technical concern and started viewing it as something that involves the entire team.
Here’s how it breaks down now:
Figure 1: A view of how people, code, and collaboration connect to shape testability.
Clean, modular, and maintainable code still matters. Without it, testing will always be more complex than it needs to be. But even the best code won’t make a difference if the rest of the development process isn’t aligned with testing.
True testability happens when QA is part of the conversation from the very beginning. That means including testers in planning meetings, discussing data and environment needs early, and defining what “done” actually means before development starts.
When QA joins the process too late, testing becomes an afterthought, and so does the quality.
Team culture plays a huge role, too. It determines whether testability is seen as everyone’s responsibility or just a QA problem. Do developers consider how their code will be tested? Are product owners open to adjusting unclear requirements?
Does leadership invest in the right tools and environments? These questions are just as important as any technical decision.
Improving Testability Without Writing Code
Improving testability doesn’t always require touching code.
Some of the most effective changes you can make are people-focused and process-oriented. Here are a few examples from what I’ve learned:
1. Use a testability checklist before each sprint. Ask questions like: How will we test this feature? What data will we need? Are the environments ready?
2. Involve QA early in the planning process. Even a short conversation during backlog refinement can save days of delays later.
3. Update the definition of “done.” A feature isn’t truly done just because it’s merged — it’s done when it’s testable.
4. Keep everyone informed. QA should be informed about architectural changes, new dependencies, or deployment plans as they occur, not after the fact.
Shifting Left – The Real Meaning
We often talk about “shifting left,” but in practice, it usually just means writing tests earlier.
- The real meaning goes deeper: it’s about planning for testability before a single line of code is written. When the whole team thinks about how a feature will be tested from the start, bugs are caught earlier, feedback loops become shorter, and releases go much more smoothly.
Final Thoughts
Testability is not a checkbox on a QA checklist. It’s a mindset, one that grows when people communicate openly, plan, and share responsibility for quality.
In my first year as a QA engineer, the most important lesson I learned was this: even the best code can’t make up for poor collaboration. If you want truly testable software, start by building a team culture where everyone asks the same simple question:
“What can we do now to make this feature easier to test later?”
References
Software Testing Weekly. (2025, September). Issue 285. Retrieved from https://softwaretestingweekly.com/issues/285
McDaniel, S. (2025). Software Testability × Test Automation: The Missing Link in QA Strategy. Medium. Retrieved from https://sanmcdaniel.medium.com/software-testability-x-test-automation-the-missing-link-in-qa-strategy-763b0aecf414