When someone interacts with a device, web site or software application, they expect it to satisfy certain criteria:

1. ✓ Give a clear starting point for the process.
   

2. ✓ Make the process have as few steps as possible.
   

3. ✓ Make each step of the process focus on one goal.
   

4. ✓ Show the progress as each step of the process is completed.
   

5. ✓ Display the result when the whole process is complete.
   

And it is the goal of an interface designer to make that happen enjoyably, through the intense scrutiny of a process, the compilation of user feedback, and flexible iteration will all involved with creating the device, web site, or software application.

This is the world of interface design...