The three-body problem, a mathematical conundrum presented by Isaac Newton and the inspiration behind Netflix’s new multi-million dollar series by the same name, can teach us a lot about mathematics… and quality assurance. Hear me out.

What is the three-body problem?

Astronomers and mathematicians have been perplexed by the three-body problem ever since humans began to understand gravity. The problem was brought to light by Isaac Newton in his Universal Laws of Gravitation, in which he tried to predict how our solar system would move over time by exploring the gravitational relationship between celestial bodies such as planets, suns and stars. To help explain the problem, I’ll oversimplify it a bit.

Imagine two planets orbiting in space. Each has a gravitational field that pulls on the other in a way that is very predictable. This means that, if you wanted to, you could work out exactly where both planets will end up at a specific point in the future. However, add a third planet to the equation, and suddenly you can’t predict their trajectories. As soon as more than two bodies are involved, the potential paths each can take can vary wildly depending on the smallest external factors. Scientists refer to this type of mathematical unpredictability as chaos.

In Netflix’s ‘The 3 Body Problem,’ this idea of chaos is explored very literally. The series follows an alien population that wants to colonize Earth in order to escape their own planet, which is caught in a three-sun solar system (ie. a three-body problem). At any one time, their planet is either peacefully orbiting one sun or in the process of being violently snatched into the orbit of another. Life fluctuates between stable and chaotic eras accordingly, making the planet effectively uninhabitable and everyone very miserable.

What on Earth does this have to do with digital quality?

Obviously, the Netflix series is a very loose interpretation of the real-world scientific dilemma, so hopefully readers will forgive me for making another tenuous (and slightly less entertaining) metaphor of my own. As a quality engineer, it can often feel like life fluctuates between stable and chaotic eras depending on which stage of the SDLC you currently find yourself in. The two bodies of price and speed seem impossible to reconcile as soon as the question of quality enters the mix. Get the balance of all three wrong and the business could suffer devastating financial consequences.

While this conundrum doesn’t go back as far as 1687, when Newton published his findings, it is still an age-old problem for everyone working in quality assurance. Whether it remains just as unsolvable, however, is a different question. In this article, I look at the best strategies for balancing speed and cost requirements against quality. But first, let’s look at the three bodies in software testing and what makes them problematic.

Body 1: Speed

Companies understandably want to have the first-mover advantage. However, the pressure to release products to market faster is only getting worse. Customer expectations are changing rapidly as new technologies, like generative AI, continue to hit the market.

In their haste, developers may cut corners in testing, opting for abbreviated test cycles or skipping certain quality assurance processes altogether. While this approach may expedite the release process, it also increases the likelihood of bugs, glitches and, ultimately, customer dissatisfaction. In some cases, developers may actually end up spending more time on hotfixes and damage control than they would have otherwise saved.

Companies that prioritize speed over quality end up with the choice of whether to release to market anyway, and risk reputational damage and client churn, or push back timelines and go over budget trying to retrofit quality (which isn’t really possible, by the way).

Body 2: Quality

Quality is the cornerstone of successful digital products. Users expect software to function reliably, deliver on its promises and provide a seamless user experience. Comprehensive testing plays a large role in making sure users are not disappointed. Developers need to look beyond basic functional testing and consider aspects like accessibility, payments, localisation, UX and customer journey testing.

However, investing heavily in testing infrastructure, employing skilled QA engineers and rigorously testing every feature before release is expensive and slow. Companies may have a superior product, but they lose the first mover advantage and may have overspent on budget that was desperately needed elsewhere.

Body 3: Cost

Quality engineers are limited by budget constraints, which can affect everything from resource allocation to investments in tooling. However, underfunding quality efforts can have disastrous effects on customer satisfaction, revenues and corporate reputation.

To deliver competitive products within a reasonable timeframe, quality managers need to use available budgets as efficiently as possible. Often, this means partnering with outside digital quality solution providers, such as those that offer crowdtesting solutions. This way, companies can test their products with an unlimited number of real users and devices globally, saving them from having to hire internally or maintain large device labs.

Navigating the QA Three-Body Problem

There is no one-size-fits-all answer to quality engineering’s three-body problem. While companies must consider the unique requirements and constraints of each project, there are some strategies that can help:

1. Clearly define project goals and prioritize requirements based on their importance to the overall success of the software product. Focus testing efforts on critical features and functionalities while being mindful of resource constraints.
2. Adopt agile methodologies that emphasize iterative development, continuous testing and collaboration between cross-functional teams. By breaking down the development process into smaller, manageable tasks, teams can deliver value incrementally while maintaining flexibility to adapt to changing priorities.
3. Leverage automation tools and frameworks to streamline testing processes and accelerate feedback cycles. Automated testing can help improve efficiency, reduce manual errors and free up resources to focus on more complex testing scenarios.
4. Continuously monitor key performance indicators (KPIs) such as defect rates, test coverage and release cycles to gauge the effectiveness of testing efforts. Be prepared to adjust strategies and priorities based on feedback and evolving project requirements.
5. Partner with digital quality solution providers that deliver a cost-effective way to scale testing capacity and simultaneously improve product quality by ensuring the involvement of real-user perspectives.

Conclusion

The three-body problem of software testing — balancing speed, quality and cost — requires careful consideration of competing priorities and constraints. Like the mathematical three-body problem, the ultimate state of the product can vary widely depending on how developers choose to balance all three aspects. Unlike the mathematical three-body problem, however, the solution is not entirely out of our grasp. It just takes considerable investment in planning, iteration and measurement.