Key Considerations:Usually written by SME's and/or Instructional Designers. There is always a clear, and important business reason for producing training video. That reason might not be apparent to the casual observer "just taking the training". But that larger business issue should inform script, scope and scale.
Technique: Be very literal and very, very clear. Ideally, "the visual" would explain and teach, even without scripted audio narration.
Results: This one is 6 years old and still gets hundreds of views a month... in Spanish!
Keys to Success: The viewer is motivated or compelled to watch this video to accomplish a clear result. Get to that result! In this kind of video "creative and clever" are usually a mistake.