The Project Management Triangle
What is the project management triangle
Also called the "trade-off" triangle, "triple constraints" of project management, "scope" triangle
The triangle has scope, cost & time, as the sides/legs of the triangle.
Project managers strive to meet the triple constraints by balancing project scope, time, and cost goals.
The practical experience here is that - when you change any one of the side / want to / need to change it, either or both of the other two will get impacted.
Example - If you want to complete the project sooner than estimated, you may need more resources/ hire a vendor, meaning more costs or you can reduce what was the original deliverable ( scope)
Before we go further , lets also take a quick understanding of the constraints
1. What is project scope
The work that needs to be accomplished to deliver a product, service or result with the specified features and functions is the project scope.
Product scope is the features and functions that characterize a product, service or result.
In the project context, the term scope can refer to either.
Let's simplify this - a bridge with relevant technical specifications needs to be built (product scope), the work required to be done to deliver the bridge (project scope). So product scope is part of the project scope.
The project manager does scope management to define what work needs to be done and then ensures only that work is done.
Project quality refers the quality of project management and that of the product - will it/ does it meet the customer specifications ( features and functions)
2. What is project schedule / time
Project Schedule includes start date and finish date for each activity. This is further strengthened by adding resources, effort requirements, milestones, dependencies.
Of-course the end date is your final target date , but cant achieve it , without managing activities and specially the ones that are critical .
Its the project manager's job to ensure that the end date for the project can be achieved and create options for it to happen, before the project execution starts. And as the execution starts, he/she ensure that the team continues to walk the line / meet the milestones to the end date
What is project cost
Project costs refer to the project budget. A project manager - estimates costs, determines budget and then controls cost.
As you can imagine/ know that cost and time are tightly linked.
Project costs are mostly the cost of resources needed to complete activities. By resources I mean - both man and material.
A project manager's job is to ensure that the project budget remains in control. This means that like for any budget - there are contingency costs build in.
4. Project constraint management
Now that we have gone the high-level understanding of scope, cost and time - we can get to the business at hand of managing the triangle.
It should be clear by now that Scope, cost and time are all planned before handsome buffer /contingency added to manage the unknowns and risk management done to ensure knowns are managed
So if you have planned and taken agreement from stakeholders beforehand- any change to the constraints- is primarily a discussion with them (post analysis) - which is fact-based - "we agreed to a timeline earlier, however since the budget has been reduced and timeline not - the scope needs to be reduced (FACTS). If we can drop X & Y features, we can remain within budget ( OPTION)" - As you can see when one (budget) is touched, scope needs be managed, to remain on time
How to manage triple constraints
Be proactive - know your constraints in the planning stage
Remember that one of the sources of project risks is thinking through constraints
Also, it is necessary - that if a big risk owing to the constraints is noted - even if you have a risk response plan for it, discuss it with relevant stakeholders. This way they prior knowledge that if they change the conditions what will happen (doesn't always stop them though)
Mostly "no" "can't do" is not a practical answer - you will have to work with the team and come up with options - meaning what can be traded off, without completely destroying expectations
Expect that something will change - most experienced project managers would agree, something will change, anytime in the project