In my opinion, video is the closest thing to a fully immersive artistic experience the digital era has been able to produce. Even in something as new as virtual, augmented, or simulated reality still use video technology to convey their visual aspects. I believe it is this very nature that makes video one of the most difficult mediums to compose in.
My own personal experience has perhaps directly influenced this perspective. For my video project I have been attempting to film my own movie, which has introduced me to all the trials and tribulations associated with content creation in the medium. Each and every detail in the process must be considered, because almost all of these details will have an observable result in the final product. Video, even when considered in its own right as a medium, is now most often paired with sound to compliment it. This combination brings out the importance of each of them simultaneously, forging video into more of an alloy of artistic mediums. I think the single most challenging aspect of creation in video is coming up with a hook. Especially in our modern digital world, the most critical component of a good video piece is its ability to keep the audience interested. And it has been a hard thing to come up with. At the end of the day it makes all the producers of video art even more respectable in my eyes.