Traffic can come from various sources. Both type-in (meaning the user thinks of the words and sees what is there) or by inbound links. Ultsearch utilizes both on a larger scale along with his own customized PPC engine to boost income. When people use domain sponsor they are only getting a small percentage of the revenue generated. You could make more money off of one good type-in than 1,000 generic visitors. Some names do not produce and are not renewed. This does not mean however, that these are bad names for other uses. Other names can slip through the cracks for whatever reason.