1. Legibility Problems

For more info on resizable text and readability, see my 2002 column, "Let Users Control Font Size."

2. Non-Standard Links

• Make obvious what's clickable: for text links, use colored, underlined text (and don't underline non-link text).
• Differentiate visited and unvisited links.
• Explain what users will find at the other end of the link, and include some of the key information-carrying terms in the anchor text itself to enhance scannability and search engine optimization (SEO). Don't use "click here" or other non-descriptive link text.
• Avoid JavaScript or other fancy techniques that break standard interaction techniques for dealing with links.
• In particular, don't open pages in new windows (except for PDF files and such).

3. Flash

Despite such good intentions, most of the Flash that Web users encounter each day is bad Flash with no purpose beyond annoying people. The one bright point is that splash screens and Flash intros are almost extinct. They are so bad that even the most clueless Web designers won't recommend them, even though a few (even more clueless) clients continue to request them.

Flash is a programming environment and should be used to offer users additional power and features that are unavailable from a static page. Flash should not be used to jazz up a page. If your content is boring, rewrite text to make it more compelling and hire a professional photographer to shoot better photos. Don't make your pages move. It doesn't increase users' attention, it drives them away; most people equate animated content with useless content.

Using Flash for navigation is almost as bad. People prefer predictable navigation and static menus.

4. Content That's Not Written for the Web

• short,
• scannable, and
• to the point (rather than full of fluffy marketese).

• answer users' questions and
• use common language rather than made-up terms (this also improves search engine visibility, since users search using their own words, not yours).

5. Bad Search

6. Browser Incompatibility

Today, however, enough people use Firefox (and various other minority browsers, like Opera and Safari) that the business case is back: don't turn away customers just because they prefer a different platform.

7. Cumbersome Forms

• Cut any questions that are not needed. For example, do you really need a salutation (Mr/Ms/Mrs/Miss/etc.)?
• Don't make fields mandatory unless they truly are.
• Support autofill to the max by avoiding unusual field labels (just use Name, Address, etc.).
• Set the keyboard focus to the first field when the form is displayed. This saves a click.
• Allow flexible input of phone numbers, credit card numbers, and the like. It's easy to have the computer eliminate characters like parentheses and extra spaces. This is particularly important for elderly users, who tend to suffer when sites require data entry in unfamiliar formats. Why lose orders because a user prefers to enter a credit card number in nicely chunked, four-digit groups rather than an undifferentiated, error-prone blob of sixteen digits?

8. No Contact Information or Other Company Info

For advice on how to best present contact info, see our usability studies of "About Us" pages and store finders and locators.

9. Frozen Layouts with Fixed Page Widths

• On big monitors, websites are difficult to use if they don't resize with the window. Conversely, if users have a small window and a page doesn't use a liquid layout, it triggers insufferable horizontal scrolling.
• The rightmost part of a page is cut off when printing a frozen page. This is especially true for Europeans, who use narrower paper (A4) than Americans.

The very worst offenders are sites that freeze both the width and height of the viewport when displaying information in a pop-up window. Pop-ups are a mistake in their own right. If you must use them, don't force users to read in a tiny peephole. At an absolute minimum, let users resize any new windows.

10. Inadequate Photo Enlargement

One of the long-standing guidelines for e-commerce usability is to offer users the ability to enlarge product photos for a close-up view. Seeing a tiny detail or assessing a texture can give shoppers the confidence they need to place an order online.

It's gratifying that most sites obey this guideline and offer zoom features, often denoted by a magnifying glass icon. But many sites implement the feature wrong.

The worst mistake is when a user clicks the "enlarge photo" button and the site simply displays the same photo. It's always a mistake to offer no-ops that do nothing when clicked. Such do-nothing links and buttons add clutter, waste time, and increase user confusion: What happened? Did I do something wrong? (An even more common no-op mistake is to have a link on the homepage that links to the homepage itself. This was #10 on the list of most violated homepage guidelines.)

Another mistake here that's almost as bad is when sites let users enlarge photos, but only by a fraction. When users ask for a big photo, show them a big photo. It's often best to offer an enlargement that fills up the most common screen size used by your customers (1024x768 for B2C sites, at the time of this writing). Other times, this is insufficient, and it's better to offer a range of close-ups to give users the details they need without requiring them to scroll a too-large photo.

Yes, initial pages should use small photos to avoid looking fluffy. Yes, you want to be aware of download times and watch your pageweight budget. Even in this broadband age, slow response times were #15 on the full list of design mistakes. But, when users explicitly ask for larger pictures, they're willing to wait for them to download -- unless that wait produces a mid-sized photo that lacks the details they need to make a purchasing decision.