^ More the vagaries and forces acting on any given market.
I don't deal, but work in the antique furniture/art trade and have seen the overall value of it go up roughly 10% a year since I don't know how long, then fall right back to what it was about twenty years ago. Nothing has changed, the furniture is exactly the same as ever it was, except nobody wants it anymore.
If you read your Wealth of Nations and accept the arguments on the Division of Labour, Use of Money, Cost of Materials and Manufacture, blah, blah, blah... You still can't factor in the fickleness of the marketeers. The clever corporate investors don't give two hoots what a company does, or it's value. They concern themselves with what all the other investors are thinking and where they will place their bets. Guess right, you take them to the cleaners. Get it wrong, you lose the lot.
There's nothing rational about it. You place your bet and hope all the other punters think the same as you, and then second guess their every move and act on it before they do.
