If your projects have ever come back to you with tripping and nuisance faults after a clean install, the problem is usually not the install. It is the settings. Settings get decided in two places, on paper during engineering and in the field during commissioning, and a lot of engineering relationships cover the first and quietly skip the second.
Three ways engineering gets handled at startup
Documents delivered, engineer gone
What it is. The firm produces correct studies and settings, hands them over, and steps away before startup.
The trade-off. It is the cheapest arrangement and the most common one. Whatever happens when those settings get loaded into the equipment happens without the person who developed them. A transposed value or a misread coordination study goes into service with nobody positioned to catch it.
Startup handled by whoever is on site
What it is. The crew or the equipment vendor enters the settings from the documents, and the engineer is available by phone if something comes up.
The trade-off. Better than nothing, and it depends on someone recognizing that a question needs asking. The failures that matter here are the ones that do not announce themselves. The system energizes, runs, and looks fine, which is the exact condition under which nobody calls.
Engineer present through commissioning
What it is. The engineer who developed the settings is on site, or reachable in real time, when those settings go live. They confirm the values are entered correctly, watch the protection behave the way it was designed to, and correct mismatches on the spot.
The trade-off. It adds engineering hours to the project, and it is the only version that closes the gap between what was engineered and what actually ended up in the equipment. For most projects the added cost is a fraction of one return trip.
Why this one lands on you
When settings are checked in the field at commissioning, the equipment behaves from day one, the client's first impression is a system that works, and the callbacks that would have traced back to a bad setting never happen. That reliability attaches to your name, because you are the one who delivered it. So does the alternative.
So when you are deciding how engineering gets handled on a job, look past the deliverable to the step that usually gets shortchanged. Ask who will be there at commissioning, and what happens when a setting has to be corrected on the spot.
A firm that treats commissioning as part of the job, rather than a document drop and a handshake, is the one that keeps your projects from coming back to you.