The importance of matching visuals to sound?

The most important thing to know is the music dictates the edit. Cuts, transitions, and effects should coincide with the flow of the music, becoming a visual extension of the song. The coordination of the music and the edit builds the overall viewing experience for the audience. The audio helps to lead and pace the changing imagery. A straight cut between two clips of video can be visually jarring, the juxtaposition of two different images is not natural to the human experience.

When a cut is synced in time to an audio hit, such as a beat in a music track, it becomes a natural transition. The same thing goes for effects and transitions that coincide with audio events, the audio carries the impact of the visual effect. A music video is a straightforward example of video coordinated with audio. When making a music video the goal of the video editor should be to craft the most cohesive integration between video and audio, effectively engaging the audience with the whole of the two parts as they become one.

Its very important to use the sync method very professionally and accurately between the visuals and sound. If it did not accurately sync all thorough out the whole music video ,then it will have a poor quality of literal meaning to the audience.

For instance in the music video 'Bohemian Rhapsody' by Queen is a performance and concept base. However, the wording of lip reading is out of place in some points of the video. I believe the reason behind this, is that the music video is an older song created in the 90's, meaning the media technology (at the stage of post production) at that period of time was more difficult and harder to create a perfect match and sync throughout a whole video.

Reference the song’s instrumentation and structure through the video’s visuals. Whenever a particular instrument or riff happens in the track it can be reinforced by the repetition of the same effect or a related visual. This doesn’t just apply to the instrumentation, structure is an important part of song writing and can be applied to video editing. Popular music often follows similar patterns consisting of multiple verses, a repeated chorus, and the use of a musical bridge to transition between key and tempo changes. The video editor should take note of these musical structures and build a corresponding visual style to match. This way the visual repetition of the music video will follow the auditory structure.
To add to that, although in the music video 'Bohemian Rhapsody' by Queen had some minor lip-syncing, there were aspects of visuals sync with sound such as instruments that are played through some shots in the video, which makes up for the slight out of sync shots as it drives the music video to keep it flowing.

The video needs to be a partner for the track and visually tell the story of the song, whether it’s a narrative or a performance by the music artist. Every frame counts in a music video and every edit needs to match up with the music in the context of the video. The music should drive the edit, with the beat often supplying the perfect moment for a cut between shots. This should be considered more of a guideline and an opportunity but not a hard-line rule. If a video were cut with a different shot coming in at every single beat it would be overwhelming, disconnecting the audience from the song.

Correspondingly, in the music video 'I Got U' by Duke Dumont uses the matching visuals to sound in a very careful and smart way, for example when the main character is shot in reality whilst he is drifted away by the headsets he bought, the music that is coming through the headsets is muted/ silenced. This creates the atmosphere of reality how music sounds like when coming out of headsets to the audience.