Is human fit the key?

I recently heard someone say, “If the user model is right, performance will follow”. The comment made think of the successful software models in the last 10 years. I am thinking of web models like HTTP, HTML, XML, and RSS. All of these had massive adoption at inception and performance followed.

I have been designing software for many years. However, I have yet to start a project by saying, “What would be the simplest model for the user?” I wonder how many do.