I keep hearing I shouldn't use contraints in Project unless I have to. Why is that?

A constraint (or a constrained task) in Microsoft Project is a task that has its start or finish date "hard coded" into the project plan. This means that the start or finish dates of the task won't change no matter what – even if it should. This can be a problem if you are running behind on certain tasks in your project, and therefore are not able to start subsequent tasks that depend on the task running late.

Microsoft Project Constraints

For example, let's say you are painting the living room in your house, and you expect it to take 2 days to get done with the first coat – but it actually takes three days instead. This means that the new start date for the second coat needs to be delayed by a day – but using a constraint would prevent this from happening!

In some cases, constraints are necessary and useful. Learn to add constraints in Project with our other post.

Predecessors in Project

The solution is to minimize (or eliminate) the use of constraints – and use predecessors and successors instead. If we link the First coat and the Second coat by the use of a predecessor, the second task is then free to reschedule if the first task happens to take longer.