That is the title of a paper written by Donald Norman, of which the last revision was published on August the 21st, 2008. In it he comes with eight design principles for waiting lines. These principles aim at designing the most efficient waiting line which is the least painful for the people in it. The interesting thing about it is that these principles apply to all services. Therefore they can also be related to the findings of the research about progress bars which we’ve published earlier.
- Emotions Dominate – This one is the most important of all. All the other principles aim at ensuring a positive emotional reaction. Here Norman draws a parallel with the waiting lines in the Disney theme parks where people are placed in pleasant and attractive surroundings, and are entertained by cast members in costumes. All this to ensure positive emotions. Because emotions are contagious, they dominate.
Get people in a good mood and keep them there. Emotions dominate everything else.
- Eliminate Confusion: Provide a Conceptual Model, Feedback and Explanation – From the start it should be clear how the line works and how people should proceed. How long do I have to stand in line and what can I expect?
- The Wait Must Be Appropriate – People should be aware of the reason why they’re waiting, and why it takes this amount of time. When people agree over it’s unavoidability, they perceive the wait as reasonable.
- Set Expectations, Then Meet or Exceed Them – For a positive experience, expectations should be exceeded. Expectations are set by ones model, of what’s going on. If people end up waiting longer than they expected, this results in negative emotions.
- Keep People Occupied: Filled Time Passes More Quickly Than Unfilled Time – This is due to the fact that how we perceive time and distance varies depending on the context we’re in.
Keep them moving fast, keep them appear to be short, keep them filled with interesting things to look at, interesting activities to do.
- Be Fair – In this case fair means that nobody has an unfair advantage. Are people helped in the same order as they arrive, or is there a way to cut in line? When a waiting-line is perceived as being unfair, negative emotions arise.
- End Strong, Start Strong – Research shows that the start and ending of an experience is critical in determining one’s memory of it. When someone’s memory of an event is a positive one, he/or she is more likely to return.
- Memory of an Event Is More Important Than the Experience – The memory of an event lasts much longer than the event itself. One’s future behavior is determined by the memories he/she has. Make sure these memories are positive.
Applying it to other services
Now have a look at the findings of the research about progress bars. The ones that where perceived as being the fastest where the ones that increased in speed when reaching the end of the bar. If you compare the principles to these findings, there is some overlap as well as some complementation.
When looking at Norman’s principles, the reason why these bars where perceived as being the fastest is probably due to the fact that they exceed expectations (principle 4). The expectations are set in the beginning (principle 7) and are based on the speed of the bar at that specific moment. When the speed keeps increasing towards the end, the user ends up waiting less time than he/she expected. But what if you would keep people occupied, or create some understanding why they’re waiting this specific amount of time? Would it be perceived as being even faster? Would it result in a more positive experience?
It’s worth to have a look at these principles while designing products, services and interactions to see how they can be optimized. Also when evaluating existing ones, they often offer good (and sometimes surprising) insight of how they can be improved. The paper can be found here on Donald Norman’s website where he publishes a variety of essays and interviews about design.