grenv: The reason to finish a jigsaw is to look at the picture I assume, perhaps show to others?

No, the purpose is merely to discover the position of the pieces. The finished article doesn't matter at all. It's meaningless and therefore pointless to waste time putting the last few pieces in place. If you want to see the picture then look at the box. it doesn't have all those quiggly lines on it for a start!

Anyway this is clearly an aesthetic endeavor, whereas a game of backgammon is a contest.

Ah, I see. So there's no possiblity that someone else could find backgammon to be anything other than a contest which has a rigidly defined ending point?

Admit it, grenv, this is your way and not the only way. What do you gain by refusing to see other people as individuals not from your mould?</i>