by Griz

Created on: May 08, 2008   Last Updated: June 22, 2009

Good, cheap, fast: pick two.

No matter what our jobs might be, many of us spend time in what we call Project Management. Those of us that don't "manage" our own "projects" probably have someone in our lives who does; someone that we go to on a regular basis and, like a kid whose mom is baking a cake, ask repeatedly, "is it done yet?" When pressed to define the term, though, we might find it a little tough. It's one of those things: you know what it is but it's hard to explain.

If you run to Webster, you'll find a project is something that is contemplated, devised, and planned. We can narrow things down a bit by saying that a project, in the sense we use the term in our daily jobs, is a set of tasks that results in a goal. In a more poetic sense, you can say that a project is what makes ideas reality.

You might be surprised to find out that an entire industry that has grown up around this concept of project management. There are classes and certifications and probably a thousand books, all with a different way of looking at the problem. Unless you're directly managing a technical project, though, you can really boil it down into a few factors that will help you understand how projects work and what helps them get done.

Projects have three factors, or constraints, that define them. The first two are time and resources. Time, of course, is how long the project will take. Resources include people, material, tools, money, all of those things that are necessary to complete the project.

The third constraint is another one of those elusive zenlike technical terms: scope. Let's say your project is to make dinner. The scope of your project simply consists of what you decide to have for dinner. If you decide to serve steak, potatoes and green beans, then the scope of your project is what it takes to put that on the table. If at some point you decide that you don't have enough time to finish the green beans then your project has a smaller scope. If you decide to add dessert, you have now expanded your scope.

You can see already with our dinner example how those three constraints work. If you change any one of them, it affects the other two. If dinner is at six o'clock, and it's four o'clock now, your time constraint is two hours. The resources required are the ingredients and at least one person to prepare them. As well, you'll need knives, a stove, pansyou get the idea.

Now, what happens if someone comes along and says dinner must be on the table by five? If the dinner of steak, potatoes, and green beans takes two hours to make then it's obvious that making a change in the time constraint makes successful completion of the project impossible. What do you do?

You have a few options. You could decide not to cook one of the dishes. That's a scope change. You could get someone to help you, or pick a different cooking method that gets the dishes done faster. That's a resource change. The cost of your project is tied to the resources (time and scope don't usually cost anything) so making changes there may change the cost of getting dinner on the table.

What happens if you change one of the constraints but don't change anything else to compensate? If we try to make a meal in one hour that takes two hours to cook, what will happen? It's going to be undercooked, poorly made, in a word: bad. Improper management of the three project constraints has caused quality to suffer.

And there's where the title of this article comes from. It's an old adage used for decades in engineering but one that can serve us well in daily life and help us remember what goes into planning projects from making dinner to putting a human on the moon. Why does it take that long? Why does it cost that much?

Good, cheap, fast: pick two.

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