The Three Headed King and the Triple Constraint
There once was a three headed king who lived a very conflicted life, for each of his heads had a different focus in life. One head always wanted bigger and better things; we will call this head “scope”. The second head always wanted to be punctual; we will call this head “time”. The third head was concerned about how expensive things were; we will call this head “cost”. The king seemed to be happiest when all three heads could balance their interests.
The king decided to add a tower to his castle which would allow him to climb to the top and view his whole kingdom. It was important to the king that the tower was completed before a big celebration in his kingdom so that he could view all his subjects as they traveled to the celebration. The king appointed a project manager to make sure that the tower would be completed while keeping scope, time, and cost happy.
The project manager was pleased with the opportunity to serve the king, yet was concerned that if he could not keep scope, time, and cost happy…heads would roll. With this challenge in place, the PM rolled up his sleeves and put together a plan which would meet the king’s needs and allow him to keep his head. He gathered the surfs together and construction began.
One day, scope approached him with a change to the original plans for the tower. He decided that since it was a long climb to the top of the tower, a lounge half way up the tower would be splendid so he could rest half way up. The lounge would be adorned with a hot tub, lounge chairs and a big screen TV. Since the king was the sponsor of the project, the PM agreed to figure out what effect this change would have upon the completion of the tower. After analysis, the PM realized that the lounge would cause a one month delay to the completion of the project and would cost one additional bag of gold.
The Project Manager realized that the change scope wanted would cause the tower to be completed two weeks after the king’s celebration and was definitely more expensive than what cost approved. With this in mind, the PM shared his analysis with the king. Immediately time and cost vetoed the request, yet conceded that the idea of a lounge would be a nice addition to the tower. The PM, being the cleaver fellow he was and remembering how nice he thought his head looked where it was, did some quick calculations and presented an alternative solution to the king. “If dear king, we built a lounge for you to rest yet only adorn it with a lounge chair, we can complete the tower in time for the celebration and for only half a bag of gold.” With that, scope, time, and cost were happy and the king approved the change.
A short time later the tower was completed with the lounge included. At the king’s celebration, the project manager was knighted…with his head intact.
The Triple Constraint
In project management there is a key concept called the triple constraint or the project management triangle. The idea is that while managing a project the PM must keep three constraints in balance; the scope or work that is required to produce the projects end results, the amount of time required to perform the work, and the cost or budget for the project. As illustrated with the three headed king, scope, time and cost are almost always competing constraints. Typically, you cannot change one constraint without affecting one or both of the other constraints.
As a sensible project manager, remember that as change happens, it is important to keep these three constraints balanced…if you want to keep your head and your job.