Radio, like television, has the ability to quickly reach a large number of consumers. The major advantage of radio lies in its ability to efficiently target narrowly defined segments of consumers. The vast array of radio program formats lets an advertiser gear ads to almost any target audience. Beyond this advantage, radio is commonly used by small businesses because it is relatively inexpensive (both in terms of airtime and production costs) and because deadlines for placing radio advertising are relatively short, providing an advertiser with increased flexibility. The disadvantages of radio are: an advertiser is limited to an audio message so there is no visual product or service identification, ad clutter can be high and exposure to the message is short and fleeting. Finally, similar to television, multiple exposures may be required for message retention and consumer action. Also, listeners may change stations to avoid commercials.