Top usability mistakes

Paul Boag

I read an interesting article today which outlined some of the top usability mistakes made by major web sites. Here’s your chance to learn from their mistakes.

Here is a summary of the major usability blunders found on leading web sites:

No search function

It is amazing that there are major web sites out there that still don’t have a search function. A usability study by Jakob Nielsen found that more than half of all users will head straight for the search function on a web site. If you have a site that has more than, lets say, 100 pages you should be looking to add search functionality.

Massive download times

Many web designer are using the increase in broadband as an excuse for poorly built web pages. However broadband usage only stands at 27%so it is important not to alienate the other 73%. There is no reason why an average web page should take more than 10-15 seconds to load. Improvements in image compression and the cleaner code produced by web standards should significantly improve download time.

Find out just how quickly your site downloads.

Non-scannable Text

People read very differently online to how they read printed material. They tend to scan web pages rather than read word-for-word. It is therefore important to provide visual elements in order to aid scanning.

Read more about this subject

Unclear linking

Probably one of the first question somebody asks when arriving at a new web page is "where can I go next?". It is important to make it clear what the user can click on. Make sure links are obvious whether textual or image based. Never leave the user guessing what is a link and what isn’t.

Poor 404 error page

As I have just covered this in a recent article so I won’t dwell on it in any great detail. However I will say that providing a helpful error page when things go wrong is an invaluable usability aid.

I have to confess it is only recently that I have come to understand the importance of this myself after reading another article by Jakob Nielsen. Users often find themselves lost within a site when it isn’t clearly marked which pages they have already visited. By simply changing the visual appearance of visited links the user has a much clearer idea of where they have been in the site and avoids going round and round in circles.

The use of frames

This could really be an article in itself. There are numerous problems with frames but some of the most significant usability ones are:

  • Pages can be unprintable
  • Pages can’t be bookmarked, nor their URLs emailed
  • The back, refresh and history buttons can become disabled
  • Visited links across frames don’t change colour

Important information contained in images

In order to have greater control over the appearance of text web designers often use images instead of dynamic text. However this creates usability and accessibility problems. Images take longer to download so those of us with slow connections have to wait for important information to appear. Those using older browsers or screen readers may find that information contained in images becomes totally inaccessible to them.

Unlike some, I am not proposing that you do not use graphical text. However I am proposing that all images should haveALT tags so the user can access that information while the page is loading.

Breaking with conventions

In my article entitled "why all web sites should look the same" I explain why web designers shouldn’t go against conventions. Users expect to find the logo in the top left. They expect to find navigation either across the top or down the left hand side. The web is incredibly confusing anyway, with every site having its own user interface. The last thing a web designer should do is add to that confusion.