I see quite a bit of confusion between project objectives and constraints.
The project objectives are:
“The objectives of a project or programme are what is required to be delivered. Objectives can be defined in terms of outputs, outcomes or benefits or any combination of the three.”
So these would include the delivery of the scope within the set timescales and budget. It could also include satisfaction of the key stakeholders with the way the project is delivered. It is important to understand the objectives before we proceed to far in the planning of the project.
This is different from a constraint. A constraint is
“Restrictions or limitations that apply to a project, programme, stage, work package etc. This could range from legal or regulatory constraints to time and cost limits.
In the context of network diagrams, this is often used as a generic term for factors affecting the possible start and finish dates of an activity including dependencies, imposed dates and resource limits.”
This is something that limits our ability to deliver the objectives. Such as the available resources, or access to a location. So we may not be able to work on a demolition at a school site during the exam season. Or we may be limited to a certain type of operating system on a corporate server.
Both definition are from the PRAXIS Framework at https://www.apm.org.uk/sites/default/files/2015/glossary-v-1-1.pdf