In many cases you can saturate the market. The stone planer examples is an early case. Cheaper lintels don't mean more windows, because they are a minor part of the cost. Cheaper doorknobs do not generate demand for more doorknobs, because the market size is the number of doors. Cheap potatoes, soy, corn, and cheese have saturated their markets - people can only eat so much.

This might also be true of web analytics. At some point, more data will not improve profitability.