I was listening to a podcast recently where Bushnell's Law was referenced: "Easy to learn, hard to master." I wasn't familiar with the Law, so I went to Google. From Wikipedia, "Bushnell's Law or Nolan's Law is an aphorism often attributed to Atari founder Nolan Bushnell, on the subject of video game design."
All the best games are easy to learn and difficult to master. They should reward the first quarter and the hundredth.
The Wikipedia page references learning curve, which is a familiar concept of knowledge as learning over time. I'm fascinated by concepts related to what I call progressive learning or progressive disclosure. As we build Reaction Commerce, we are designing it to be simple enough to use by non-technical business owners, but powerful and customizable for technically-minded individuals and teams. The idea of rewarding the first quarter and the hundredth is powerful. It's hard to do, and the example of video game design is a good one for me to consider and research.