All of the above. 1500 bottle wine cellar, frequent tastings, bottle variation even with the world's finest crus of same producer and vintage, many more vagaries in viticulture than audio engineering. And let's please not even mention any aspect of human relations, which are not, ahem, "hobbies." But tweaking an audio system can take forever, as the Nth degree recedes endlessly, "boats against the current." Unless you're millercarbon, who has got everything right, a fact I acknowledge with the greatest respect and admiration. What's left after that but to read The Brothers Karamazov in Russian, Tale of Genji in Japanese, Proust in French?