copied from source - Wikipedia
“music video is a short film or video that accompanies a complete piece of music, most commonly a song. Modern music videos are primarily made and used as a marketing device intended to promote the sale of music recordings. Although the origins of music videos go back much further, they came into their own in the 1980s, when MTV’s format was based around them. The term “music video” first came into popular usage in the early 1980s. Prior to then, such clips were described by various terms including “promotional films” or “promotional clips”.
Music videos use a range of styles of filmmaking, including animation, live action filming, documentaries, and non-narrative approaches such as abstract film. Some music videos blend different styles, such as animation and live action.
Since December 1992, when MTV began listing directors with the artist and song credits, music videos have increasingly become an auteur’s medium. Few if any filmmakers train specifically to make music videos, and very few can afford to make them exclusively. Most split their time between videos and other film projects. Music video directors - who generally conceive, write, and direct their videos - currently receive no authorship, creative rights, profit participation or residual income from DVDs, iTunes, and other new media on which their work may appear.
However, those features of the industry that tend to make music video direction a less-than-lucrative profession, have also made the medium an exciting art-form, one defined by the cross-pollination of ideas and approaches from various disciplines. Music video directors, like most filmmakers in general, emerge from disparate backgrounds, and don’t share much in the way of common thinking or set-in-stone pedagogy, bringing to the field a diversity of experience.”
The idea that a music video is simply a means to make money features heavily in this buisness but my opinion is that a music video should be made to promote the bands sound and the song which the video is based on , not just to see how much money you could make.