Project trade-offs are the best technique to use when you’re dealing with executives who want to make changes to the plan. Knowledgeable project executives understand the concept of balances or trade-offs when they want to add or delete something. They know that if they ask you to squeeze the duration by one month it will affect the scope, cost or risk. Those are the 4-corners of a project.
Unfortunately, there are other executives who think they can shorten the duration of the project by a month without impacting the other three corners. In this project fantasyland, they believe they can increase the scope and the deliverables without affecting the duration (schedule), cost or risk. They think any changes they want to make to the project are “free.”
Project managers who allow project executives to live in this fantasy world are doomed to repeated project failures. Once you give the executives free changes to the project, they will continue to request (or demand) more changes.
Using the 4-Corners
Skilled project managers always talk to executives about trade-offs between the project’s 4-corners: scope, duration, cost and risk. They make the point that there are no “free” changes. Every change to the project impacts the other corners and requires a trade-off. But tactically, the PMs never say “no” to a change. That never gets them anywhere. What they say is, “Yes, I can change the schedule to finish two weeks earlier. But that will increase the project cost by $14,000 to pay for overtime and hiring several consultants. Do you want to do that, sir? Do you want to trade off a two week earlier finish for a $14,000 increase in the budget?”
Project managers should talk trade-offs with executives during the initial planning and in the approval presentation. They should continue this discussion every week when change requests are submitted and as variances appear.
They also always have the data on the 4-corners and always carry an iPad or small PC so they can generate tradeoff data in a minute or two from their MS Project schedule. You need to quantify the scope, budget, rick and duration.
We teach this tradeoff technique in all our beginner and more advanced approach in our advanced classes. You can also read more on quantifying the 4-corners in our articles of risk management, scope definition, budgeting and scheduling.