The Triple Constraint (aka, Iron Triangle) is often regarded as a law of physics. A change in one side of the triangle, by definition, affects another. An increase in scope must either result in higher costs or longer timelines. Conversely, reducing time or cost requires a similar reduction in scope.
Previously, I argued that we should question gravity and invert the Iron Triangle paradigm. The relevant project constraints are time and cost, not scope—they drive most projects. The Project Box illustrates this new paradigm. Time and cost are fixed, quality is “good enough,” and scope is variable.
In this article, I propose that we can “cheat” the triple constraint by becoming more efficient and productive. Traditional project planning assumes a known and steady development rate, which is a strong assumption. By changing how we work, we can get more in less time.
The Triple Constraint
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Large Defense and NASA projects in the 1950s struggled to manage performance trade-offs. Dr. Martin Barnes simplified everything when he introduced the Iron Triangle in 1969. The model was intuitive.
A project to dig a 200-yard ditch offers an opportunity to demonstrate the triple constraint in action.
- If one person can dig 10 yards per hour and is paid $10 per hour, the estimated duration is 20 hours, and the cost is $200.
- If two people work on the project, the job can be completed in half the time at the same cost.
- If the project scope expands from 200 to 400 yards, then the estimated time and cost will double.
The foundational assumptions and inherent shortcomings of the simplistic model are apparent:
- A single digger might not work at a steady pace. They may dig faster early in the day and slow down as they get tired.
- If there are multiple diggers, they might receive different pay and work at different speeds.
- Eventually, adding more diggers becomes ineffective. If there are 100 people, they will be bumping into each other.
- The ability to innovate, improve, automate, and become more efficient is not part of the model. One person with a backhoe can dig the ditch in a fraction of the time.
While some aspects of the Iron Triangle may apply to construction projects, they are questionable when it comes to technology and knowledge work. Frederick Brooks wrote The Mythical Man-Month in 1975, describing his experience leading a large systems project at IBM. Even then, he recognized the folly of the Triple Constraint. He noted, “When schedule slippage is recognized, the natural (and traditional) response is to add [people]. Like dousing a fire with gasoline, this makes matters worse, much worse.”
A corollary to the Iron Triangle is the trade-off between speed and quality, which has been proven to be a fallacy. The 2017 State of DevOps Report demonstrated that high-performing teams delivered software more quickly and with fewer failures than lower-performing teams. The Scaled Agile Framework promotes its benefits as faster time to market, higher productivity, and fewer defects. We can be better, faster, and cheaper.
Cheating the Triple Constraint
Understanding the limitations of the Triple Constraint creates the opportunity to exploit the cracks and cheat the system. Sponsors, customers, and project teams can have healthier and more productive conversations. The goal is to achieve higher satisfaction by meeting expectations and lowering frustration among all stakeholders.
Lean Out the Process
Improving productivity or implementing process efficiencies will bend the time and cost curves. Many options and strategies can be employed that will have both immediate and compounding impacts on the project. Eliminating waste will have a profound and lasting impact.
Waste is defined as anything that does not directly generate value. Motion, extra processes, defects, and waiting are forms of waste that are easy to find and fix. Cultural problems are more pernicious and harder to root out.
The first step is to create a value stream map of the process. List the steps, evaluate them, then begin to measure their efficiency:
- How does each process contribute to the final product or service? Is it mandatory? Does it improve execution? Or can it be removed?
- How much time is spent on that process? What is the ratio of productive work to the total time?
- How many people are involved in the process? Are they all necessary?
Let’s assess reviewing requirements or design documents. Ensuring that requirements have been captured and that the design is feasible is critical. However, many organizations have ineffective processes.
A week or more may be allocated for document review. In reality, people spend only a few hours preparing for the meeting, if at all. Comments lack substance. Precious time is wasted.
To improve, remove unnecessary steps and people from the process. Reduce hand-offs and waiting times. Shorten decision-making cycles.
Amazon takes a radically different approach to documentation and reviews. Long-form written 6-page memos replace PowerPoint presentations. The first 20 minutes of a meeting are reserved for reading the document. This is followed by a structured review and feedback session. The process encourages deeper thinking and collaboration.
Manage Differently
Working harder or faster is the traditional approach to increasing productivity. Frederick Winslow Taylor, one of the most influential management thinkers of the 20th century, believed that management should set the pace of production. Henry Ford designed his assembly lines based on Taylor’s ideas.
Productivity monitoring software gained widespread use during the COVID-19 pandemic. The performance of knowledge workers like lawyers, consultants, and software developers is measured by keystroke counts or the number of code check-ins. These measures may result in short-term improvements at the expense of quality, creativity, and worker well-being.
Reinforcing the Iron Triangle by focusing on output is not effective. Embracing the Agile principles of building motivated teams, pushing decision-making down, and fostering psychological safety will lead to breakthrough performance. The Gallup Q12 survey consistently finds that engaged employees are more productive and their companies are more successful.
A large systems development project was months behind schedule. The project manager had a traditional approach. During the weekly status calls, team members were interrogated and reprimanded for missing deadlines. Things got worse instead of better. Eventually, a new project manager was hired. Micromanagement was replaced with empowerment. While the team did not make up the lost time, they started hitting milestones and completed the project on their revised and new, realistic schedule.
The Allure of Automation
Automation and technology create opportunities for significant gains in productivity, enabling more work to be done more quickly. The Agile DevOps movement emphasizes the value of automated testing, continuous code integration, and continuous deployment. The benefits can be dramatic—10X faster test execution, 4X increases in monthly deployments, and over a 250% return on investment.
AI has the potential to remake our project environments. Software engineers use it to help them write code. Non-developers are using the tools to write small programs, too. The level of effort to research, analyze, and synthesize information has already fallen dramatically. Early data indicate an average of 4 hours per week saved by using Microsoft Copilot. And we have only begun to scratch the surface of its capabilities.
© 2025, Alan Zucker; Project Management Essentials, LLC
See related articles:
- Create Value: Map the Value Stream
- Eliminating Waste in Knowledge Work
- Flipping the Triple Constraint
- The Evolving Arc of Management
- The Project Box—Evolving Beyond the Triple Constraint
- Questioning Gravity: Is the Triple Constraint Really Relevant?
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