Six years ago, when The Farnsworth Group asked builders to tell which attributes of a building material supplier counted most, having quality products topped the list. But that was before the housing crash forced contractors to fixate on the product’s price. By 2010, price matched availability as most desirable. Then last December, when Farnsworth asked 162 builders to divide 100 points among five attributes, availability scored highest. Why? The Farnsworth Group suggests it might be because contractors who went to big boxes in search of low prices discovered that many goods they wanted weren’t on the shelves.