The most important reason in what makes a good music video is to avoid 'viewer fatigue', and there are a number of ways of doing, firstly by the lip synching to being absolutely perfect and that the person performing is full of confidence, to engross the viewer into watching the music video.
One way to defiantly avoid 'viewer fatigue' is by using varied shot types and angles. For example in, Katy Perry's T.G.I.F, there are a number of different shots in the video, from an establishing at the beginning to almost set the scene for the viewer and to an over-the-shoulder shot showing that a conversation is occurring, making it a lot more interesting. Also, there are the basic shots of a close-up and a long shot keeping the video simple. Although, there are a few long shots that are very interesting as in the background it is full of people and then in the foreground it has Katy Perry as the main subject, as it looks like a perfect picture making it more exciting for the viewer.
Another way that makes a music video good is by the change in costume and location, and the example of Lady GaGa's Judas does this very well. From beginning to the end there are a number of costume changes like the motor bike style in leather to her dancing in a red bikini. Also, Lady GaGa links some of her costumes to her song, because as the song is called Judas she wears a vicar style top and a cross necklace linking to the song. She also changes locations throughout the music video, keeping it more interesting for the viewer and she largely avoids 'viewer fatigue' in this video.
So overall, what makes a good music video is to change the music video throughout, even if it's by changing the mise-en-scene, the lighting, the costumes and camera angles/movements. Also, having a confident performer and good lip synching is vital to make a good music video that avoids viewer fatigue.
So overall, what makes a good music video is to change the music video throughout, even if it's by changing the mise-en-scene, the lighting, the costumes and camera angles/movements. Also, having a confident performer and good lip synching is vital to make a good music video that avoids viewer fatigue.