For double the effort, which not many people go to.
Documentation is hard. Good documentation is harder. There are many occasions where video and video-like things are good for getting a feel for something and just plain text is good for reference. We shouldn't be saying "just use text because you probably won't bother doing everything you should". We should be saying "Hey, video, still images, and text all combine to make great documentation and help people to understand and use your tool / product." They take time, but we should care about our users, and thus we should take the time to support them.
That's how I did the animations for this Powershell tool.