[IxDA Discuss] Common design mistakes?

[Bryan J Busch]

> I am thinking of putting together a half-day course for CHI 2007.  As
> I prepare for it, I'm curious about something.  What, in your
> experience, are the most common design mistakes made by novice or
> untrained designers?  (Or those most likely to be taking an
> introductory CHI course?)

Here are a few selections from my holistic usability checklist that  
might apply, written in the style of "things that should be true":

* Forms use visual styling to reinforce which fields are required,  
for instance a colored border on a text input box.

* Users can easily tell which fields can be used to sort data in a  
table, and specifically those that are currently sorting.

* All major text and link colors have sufficient contrast (http:// 
www.snook.ca/technical/colour_contrast/colour.html) with regard to  
the background color "when viewed by someone having color deficits or  
when viewed on a black and white screen".

* The body copy font size is large enough that users with visual  
disabilities would likely have no trouble reading it (e.g. larger  
than 9 "pt").

* Text links have a hover state declared such as changing the text  
color or adding an underline when a user hovers his/her mouse over a  
link (though we recommend avoiding a changed font weight or font size  
on hover).

* Text links use a different color than regular body text.  
Underlining can be reserved for special uses.

* Navigation and sub-navigation have different display properties for  
the page that is currently being viewed. For example, if one were  
looking at the "Services" landing page, the "Services" link would  
appear differently than the other links in the main navigation. This  
establishes the current location for the user.

- Bryan