When the measuring happens first, install day is execution, not discovery. Turf arrives already cut to the plan, with materials counted to the square footage. The old lawn comes out first, sod, roots, and enough soil to make room for the base, and gets hauled away.
Then the part nobody sees but everything depends on: the ground is graded to move water where it should go, and crushed base rock goes down and gets compacted hard in layers. Only then is the turf rolled out, seamed, trimmed to the edges, and fastened around the full perimeter. Infill is dropped and broomed down into the fibers as the final step, standing the blades up and weighting the whole surface. A walk-through of the finished yard against the agreed scope is the check worth doing before any job is called done.
Post has judged materials before. The Postex Cotton Mills that opened here in 1913 were turning out six million yards of cloth a year by 1945, and a mill town's eye for fabric translates directly to turf: face weight is ounces of yarn per square yard, pile height is measured like nap, and the backing is the weave that holds it all together. The difference between a ten-year yard and a three-year yard is in those numbers and in the base below them, which is why both belong in the scope on any bid.