[IxD Theory] Foundational Principles

Are some of the foundational principles more important than others? If so, which ones? Why are some more important than others? Can you point to examples that illustrate the hierarchy you propose? Consider both Neilson’s and Norman’s lists.

I do not think the answer to the first question in this prompt is fixed; which principles are most important really depends on the application and the goals of the interaction. The question of who will be experiencing the designed interaction (Who are the users?) and what is their connection with the experience (eg. Are they likely to be novice or expert users?) should guide which principles will be most important. For example, if you are designing a museum exhibit, then you can probably be less concerned with "Recognition rather than recall" and more concerned with "Affordances" and "Mapping."

That being said, I do have some pet principles that I am particularly drawn to. From Nielsen's list, I like Flexibility and efficiency of use and from Donald Norman I like the principle of Mapping.



Flexibility and efficiency of use
This principle is about allowing the interaction to be tailored to both the expert user and the novice user. The impact of this principle is illustrated when you examine the keyboard shortcuts available in Adobe CS software versus the shortcuts available in Microsoft Office software. Adobe CS has keyboard shortcuts for the most common actions and within the Keyboard Shortcuts preferences, every single menu command can be assigned a shortcut. This flexibility allows for expert users to set controls for the actions they perform most often and in doing so increases efficiency. In contrast, the Microsoft Office suite does not have very many keyboard shortcuts and does not allow for any customization. Recently I was editing a client's 30+ page PowerPoint presentation which had objects on every page that needed to be aligned. For each group of objects I had to go through three menu steps. The ability to set a keyboard shortcut for "left align" would have been so, SO, appreciated.

Mapping
In this case, mapping refers to the relationship between the movement of controls and the result in the real world. A good example of mapping would be the progress bar on streaming videos. When the cursor is moved to the half way point on the progress bar, the movie skips to halfway through the video. Moving the cursor backwards moves the video backwards. The relationship is clear and intuitive. Mapping has the potential to take a product with lots of features and capability and make it simple by making it easy to use.

I think the key to both of these principles is showing respect for the time and needs of your end users.