Both of these methods cost much less than making calls with live sales agents. Making a voice broadcast call in the U.S. costs one or two cents. The voice broadcast call does not have a significant labor cost (a $20/hour sales agent consumes $0.33 per minute). Live sales agents are expensive, so telemarketers using live agents will purchase marketing lists that identify good demographic targets. Voice broadcast marketing is cheap enough that marketers may not bother purchasing marketing lists. Voice broadcast marketing only needs live agents for those prospects who express interest in the product by pressing "1" or calling back.