Flakiness in automated testing: Why your tests keep failing intermittently (and how to solve it for good)
If you’ve ever seen your automated tests pass one day and fail the next without any code changes, you’re not alone. At Fusion IT, we’ve seen how test flakiness can frustrate teams, slow down delivery, and shake confidence in QA processes.
This issue isn’t just annoying it has a real business impact. The good news is that it can be solved with the right technical strategies and the right mindset.
What is flakiness really?
Flakiness happens when tests produce inconsistent results, failing and passing unpredictably, without changes in the code or test logic. This creates unnecessary noise in CI/CD pipelines, leads to false positives, and wastes valuable time.
From our experience, flakiness is one of the main reasons teams stop trusting automated tests, which creates a major risk in fast-paced delivery cycles.
Common Causes We’ve Seen
- Race conditions in code or test logic
- Unstable dependencies like external APIs or databases
- Poorly managed persistent state, where data from one test affects another
- Fragile UI selectors that break with small interfaz changes
- Environmental inconsistencies, especially in shared test environments
The first step toward solving flakiness is understanding its root causes.
How to Measure Flakiness
Before you can fix it, you need to measure it.
- Key metric: Flakiness Rate → the percentage of tests that fail at least once and then pass again without any code changes.
- Recommended tools: Azure DevOps Analytics, Allure Reports, or custom dashboards tracking test trends over time.
At Fusion IT, we encourage teams to integrate flakiness tracking directly into their pipelines. Visibility is essential for long-term improvement.
Strategies That Actually Work (From Real-World Experience)
At Fusion IT, we’ve helped teams cut flaky tests by more than half within just a few sprints. The key wasn’t a single silver bullet, but a combination of practices that we’ve seen consistently deliver results:
- Test Isolation → Each test runs in its own environment, with no “hidden” dependencies. This prevents one unstable test from contaminating others.
- Stable Test Data → Controlled, versioned datasets make every run predictable, eliminating the “it worked yesterday” excuse.
- Mocking and Stubbing → External services (APIs, DBs, queues) often cause noise. We simulate them where needed, keeping pipelines stable without losing realism.
- Smart Retry Logic → Some failures are truly intermittent. We retry them with clear thresholds and alerts —making sure retries don’t mask real defects.
- Testing Observability → Deep logs, traces, and metadata capture every step, so when a flaky test does appear, root cause analysis takes minutes, not hours.
Most importantly, we’ve learned that technical fixes only last when QA and DevOps work together. Sustainable test stability comes from collaboration as much as from tools.
Where to Start
If your team is drowning in unreliable tests, here’s a practical starting point:
- Measure your flakiness rate → quantify how many tests fail inconsistently.
- Spot the patterns → review failures from the last sprints, look for repeated offenders.
- Tackle the high-impact tests first → focus on those failing often or blocking CI/CD.
- Stabilize your dependencies → mock or stub external systems in your CI environment.
- Define “stability” as a quality gate → make it part of your definition of done.
With these steps, you’ll not only reduce flakiness but also rebuild confidence in your automation suite.
Our Perspective at Fusion IT
Across industries, we’ve found that flakiness is one of the most persistent QA challenges. The teams that solve it share two traits:
- They invest in test quality, not just test coverage.
- They set up a clear process to detect, track, and eliminate flaky behavior.
Flaky tests drain energy and erode trust. But with the right practices, that trust can be restored and your test suite can once again be a reliable, strategic asset that accelerates delivery.
Need Help Improving Test Stability?
If your QA team is spending more time chasing false failures than preventing bugs or improving coverage, we can help.
At Fusion IT, we specialize in building test pipelines that are fast, stable, and transparent. Whether you need to optimize an existing setup or design a new one from scratch, we work with your team to create a testing strategy that scales.