Something that I aim to learn. My uneducated view, is that once the basic's have been understood i.e. direction of spokes and lacing patterns, dish, round and true (my basics!), it's probably not too hard to build a wheel, follow a sequence and there it is!
However, I regard being able to build a good wheel to be a much more difficult/skilled thing to achieve!
A black art, where with time and practice and use, the dextrous, mechanical hand-eye skills blend with experience and understanding, experimentation, failure and success to enable the wheel builder to become a true crafts-person.
By which I mean someone who is able to interpret their own or another rider's subjective and/or objective requirements, where their developing understanding of which rim profiles are best combined with which spokes and hubs and are able to feel how they can use spoke tension to give a wheel that feels right to the rider.
Or maybe Im getting carried away with the romance of it all?!