There is nothing inherently wrong with the preorder model...
As far as miners are concerned, almost everything is wrong with the pre-order model.
It encourages operations like HashFast, players who enter the manufacturing field risking none of their own money. If their gamble pays off, they become rich. If it doesn't and the company fails, the actors have lost nothing, while profiting from the money they have paid themselves and their friends in salaries.
The problem is that no one has stepped up and sued one of these companies for fraud. Both BFL and Avalon should be out of business by now but they know their customers are lazy.