The more complex something is, the more controls it needs, whether visible or invisible to the user.

• From the user's view, products and services are automated. If you stay at an expensive hotel, your room is always as you want it. The staff handles the complexity beh...

A conceptual model is the underlying belief structure about how something works.

For example, on many computers, the process of dragging and dropping files into a folder seems simple because people already understand physical files and folders. But understanding it is...

"The total complexity of a system is a constant. If you make a user’s interaction with a system simpler, the complexity behind the scenes increases."

• How simple something looks is not a reflection of how simple it is to use. If complexity is a constant, then there are trade-offs.
• Things don't always need to be very simple for users. When a product or service is too simple, users can feel robbed of control. We should recognize th...