What makes a website usable? It’s something that Dr. Jakob Nielsen, principal of the Nielsen Norman Group, has devoted his life to finding out. He specializes in “fast and cheap” improvements of user interfaces and holds 79 U.S. patents, mainly on ways of making the Internet easier to use. He holds a Ph.D. in human–computer interaction (HCI) from the Technical University of Denmark in Copenhagen and has worked for companies such as IBM and Sun Microsystems. He also may be the only person whose official bio page includes a list of the Internet sites that have made fun of him.

What’s the biggest usability mistake you see in corporate web design?

Not getting to the point. Beating around the bush. Corporate websites have big pictures of things that people don’t care about that delay them in finding the answers to their questions. Or the websites don’t even answer their questions. The one thing users ask the most is, “What‘s the price?” and it’s amazing how often you can’t see the price.

This happens particularly in business-to-business sites. Users are getting very accustomed to sites such as Amazon for having a pretty straightforward way to do business online. With B-to-B, instead of spending $20, they’re spending $20,000, and it’s harder to find the price.

We were delighted to see that your book was called Designing Web Usability: The Practice of Simplicity. How does simplicity enter into web design and usability?

By cutting away things that people don’t need, you focus their attention on the smaller amount of information and the smaller number of features. Everything added to the interface is something else users could do wrong or that could get them in trouble. Shaving away stuff hones design.

From a business perspective, it means that users can concentrate their brain power on products and the message, rather than mechanically operating the user interface. A cognitive interface, complex designs, lavish designs—all of that ends up hurting the business, as well as annoying the customer. Every extra feature, picture, anything you put on the website or interface is one more thing that could go wrong, that people have to look at, consider, possibly use wrong, and convert them from the core thing they want to do.

You’ve come under some criticism for some of your views, such as a couple of years ago when you said the best way to design mobile sites was to use different features than ones used on desktop sites. How has that turned out?

History has a tendency of repeating itself. Every time a new technology comes out, it is abused and used in ways not for users. Studying users—not the technology—raises warning flags. People enamored of the technology side will criticize us. They will say we think people are too stupid or too lazy. It’s not that they’re stupid or lazy, but they don’t care about technology, they care about getting their jobs done.

For mobile websites, users do need different designs for a tiny phone as opposed to a big desktop computer. There’s an ideology to say that you can do the same thing everywhere, but that’s wrong. And that’s been vindicated by many examples. For example, Facebook had a very hard time with mobile because it didn’t have a mobile app.

Now, design is more often having separate designs for desktop computers and phones. Generally speaking, now the tendency is toward trying to do a little bit more for optimization of each of the platforms, because they are quite different.