Grey Lynn picket fence

That is the part worth explaining. The moment a picket is fixed in place, the back of it, the two ends and the faces where it meets the rail are gone — nobody is ever coating those again. Water does not care that they are hidden, and end grain draws it in faster than any other part of a fence. So the timber was primed with an oil-based wood primer while it was still flat, still loose, and every face of it could still be reached. Getting that into the build sequence took one conversation with the builder and cost nobody a day.

Then it went up, and the detailed work started. A picket fence is almost entirely edges — every picket has two faces, two long edges, a shaped top and two rail junctions, and all of it has to be worked by hand. There is no open run to move through, just the same small set of surfaces repeated a few hundred times, and the finish is only as good as the most rushed one.

The grain was filled and sanded back flat, because on a fence at this standard raw timber grain will telegraph straight through a topcoat and you see it in every raking light for the rest of the fence's life. Every junction and gap was sealed after that — not for looks, but so the fence is closed up and there is no path for water to sit in behind the coating.

Then three top coats in Half Alabaster, semi-gloss. Filled, sealed and laid off properly, there is no grain left in the surface to break the sheen — it runs clean and unbroken down the full length of the fence. The owners have a fence that looks the way a new one should, and is protected in the places nobody will ever see.