An abstract house is a house that is incomplete.
The walls may be complete, but if one component is incomplete, say the roof, then we only have an abstract house. We have to say that the entire house is not finished -- let's not use that word, let's say that the entire house is not defined. The roof has not yet been implemented. I may put on a different type of roof than someone else.

How's that analogy?

If the house is finally completed....aah that doesn't work. Usually people can add extensions to rooms, inheriting the main design. Final may be like when you can't add any more rooms due to zoning/compiler rules.

Anyway, you said you figured it out.