A software-animation or screen-cast is a digital recording of sequential screenshots. It is like a movie of what a user sees on the screen while working, with or without additional explanation (voiced-over or through text boxes).
Ideal for explaining software.
Choice of tools: availability of all kinds of tools, open source as well as commercial options.
You can easily create a screenshot / screen-cast on your own PC.
You can erase and replace less successful sections yourself using the tool.
Preparation (developing a good script) takes time.
Learning to use the tool takes time. Most tools have a fairly steep learning curve.
Finishing (deleting the less successful parts or replacing them) takes time.