Naoman Sheikh, a project manager currently working with Virgin Media to expand the reach of their Triple Play Services (Digital TV, Broadband and Telephone) to the far corners of the UK.
The Triple Constraint is a pretty fundamental concept to the theory of project management. Imagine, if you will, a triangle with Time in one corner, Cost in another and Quality in the last (I will add a diagram later if I can be bothered).
The basic premise of the triangle is that you cannot change one factor without adversely effecting the other; if the Time it takes to deliver a project is to be reduced then the Quality of the product the project is due to produce will have to be reduced and the Cost will have to increase (in order to employ additional resources or services to complete the project quicker). If the Quality of the product was to increase then it is likely that it will take longer to produce (Time) and that it will, invariably, Cost more. If Cost was suddenly reduced then the potential impact is increased Time and reduced Quality.
The Triple Constraint is often used to determine if a particular project is still viable e.g. should the project be terminated if the increased amount of money cannot be found? The output of the project was due to give the company a competitive edge. Will the competitive edge still be valid if the project takes two more months to deliver? Projects can literally live or die based on the Triple Constraint.
This is actually quite a simple concept but a very powerful one if used in the decision making process. Personally I find the Triple Constraint invaluable for when I receive any change to a project. I’ve become so accustomed to it that I automatically go through the motions in my head every time I receive a change. All good project managers should do this. If you do not do this, and you consider yourself to be a project manager, you are not.
So you get it, right? Pretty simple, right? I’m sure you’re expecting me to say something really smart and completely do away with the Triple Constraint. Nope. But I would like to introduce a new ‘corner’ to the Triple Constraint that is reviewed alongside the others; Benefits. Were you expecting something more grandiose? If so, click here.
All projects are initiated because a positive benefit (usually to the company) is expected upon completion of the project. For example, an organisation has initiated a project to be the first to market with a blue widget cranking machine. The world has never seen such a thing. Analysis of all well known competitors shows that none have the magic ingredient to make the blue widget cranking machines. Being the first to market will give them a competitive edge and will result in an increase of 100 new customers; Benefit. The project is initiated. Half way through the Execution phase, there is an announcement that shakes the project to it’s very core. A little known company in Uzbekistan brings a blue widget cranking machine to market; they’re the first. The project manager and the project board meet to assess the continuing viability of the project.
They realise that they could reduce the Time it takes to bring the blue widget cranking machine to market by decreasing the Quality and increasing the budget (Cost). This may very well be possible but is it the most viable thing to do. This is where the fourth constraint comes in; Benefits. So the project above was conceived to be the first to market with a blue widget cranking machine the net result of which would be an increase of 100 new customers. Is this still the case? Will the Benefits still be realised? The answer is a simple no. Another company is the first to market and the customers have probably all gone to them. However, it would have been much more difficult to arrive at this decision with just the original factors of the Triple Constraint as the focus is mainly on delivery and completion. Now this does not mean that the project should be terminated but it does mean that the project should be put on-hold and the original business case reviewed to identify alternative and viable benefits if the project was to continue.
In summary, use the Triple Constraint every time a change is made to your project but also ask yourself how this particular change effects the Benefits the project had originally set out to deliver.
PS Yes, I know I have an unhealthy obsession with widget cranking machines.
May 19th, 2009 @ 1:01 pm
Great post Naoman !
May 19th, 2009 @ 2:03 pm
Your benefits corner is a function of quality.
May 19th, 2009 @ 2:46 pm
Indeed a powerful model…. if used!
Here’s what I experience though – decisions/course corrections when a project is mid-way are often taken without considering one, or even two, of the other corners. Then when low-quality is experienced, or increased costs, etc… guess what? Project sponsors are surprised!
Why are they ignored?
Because it produces an unpalatable answer.
Or because it shows a lack of heroism.
Or because it isn’t exciting.
Or because decision makers are lazy.
The corners are generally well considered during project planning, but in my experience, they soon get forgotten as a triple constraint once the project is under way.
May 19th, 2009 @ 8:00 pm
Good Article Naomey.
A very basic model which should be used in all projects.
Your humour needs to have the model applied to it too
May 20th, 2009 @ 12:19 pm
Naoman,
Lot’s of talk (and writing) about the Triple Constraint right now — ahead of the new PMBOK version increasing the “legs” of the triangle.
This is one of the better pieces.
There have always been more constraints in projects than three. It’s refreshing to see people (and PMI) starting to think this through in a creative way on the path to a better model.
Thanks,
—www
May 20th, 2009 @ 1:16 pm
William: yes PMBOK v4 is balancing against a lot more constraints than the triple one which in my mind is very limited (Just consider the “risk” axis).
Regarding the Benefits. In Prince 2 it is I guess the Business Case, that needs to be reviewed as necessary. In your example when something change should it be outside or inside the project.
In the end that’s ONE more thing to deal with as a Project Manager, not only making sure that execution goes OK but that the project still make sense!…
May 20th, 2009 @ 2:25 pm
Thanks for the great comments, I think this is a particular element of Project Management that is often seen to be quite rigid and stiff but in fact is actually very malleable depending on the type of project you are managing.
@www Thanks for the compliments. You’re right, in some respects the triple constraint ends up being a constraint for the project manager. I have come across some PMs who focus solely on the triple constraint and some that don’t at all, both are incorrect.
@vincent I’m not sure I understand the question correctly but if I understand it correctly then I would say that no matter where the change comes from, inside or outside, the impact should be assessed.
@simon Yup, I couldn’t agree more. Turning around and saying “Is this project still viable?” is the last question anyone wants to hear, including the PM! But the question must be asked.
@Sam and Bryan H Thanks
May 20th, 2009 @ 3:02 pm
I like the idea that Naoman identified a fundamental drawback of the Triple Constraint Model and proposed a thoughtful solution. As noted in one of the replies, there may be even more legs to this “stool,” such as risk.
Let’s consider this for a moment, a five-legged stool. Can you see where I am going?
Though I agree the model is flawed, I don’t agree that making it more complex is the answer. So in the hopes of keeping the model simple, I suggest the flaw lies in the legs themselves.
I offer these 3 legs instead:
- Speed
- Value
- Performance
Reflect on those for a moment and let me know what you think. I believe these dimensions factor in speed-to-market, benefits and risk (risk being a subset of performance). I will likely write a post on my blog, inspired by this discussion, so please comment there as well.
Steve Romero, IT Governance Evangelist
http://community.ca.com/blogs/theitgovernanceevangelist/