Increasing traffic.

As well as increasing revenues, a satisfied customer brings free word-of-mouth exposure-bringing more buying customers to the site.

"In our first year we didn't spend a single dollar on advertising, but we grew real big just on word of mouth. The best dollars spent are those we use to improve the customer experience."

-- Jeff Bezos, Amazon.com

Increasing 'conversion rates'.

The conversion rate is a driving force for new business - whether that is a user requesting information, subscribing to a newsletter, or purchasing something. For e-commerce web sites, raising the conversion rate by 1% can add considerable returns.

Protecting market-share.

Conversely, a bad customer experience can cause a customer to abandon a site permanently. That customer may go even further and advise people not to use it. Your competitors are only one click away.

"The customer experience is the next competitive battleground."

-- Jerry Gregoire, CIO Dell

Competitive advantage.

Many leading corporations such as IBM, Apple Computer and Microsoft are incorporating usability into their product development cycles because they see it as a core differentiator in a highly competitive market.

As Karat (1997) said, "companies committed to ease of use do more than meet customer expectations; they can actually exceed anticipated earnings."

Improved productivity.

If the interface is well designed then this will allow the users to concentrate on the task at hand rather than the tool. This enables users to operate effectively and efficiently, rather than lose vital time struggling with a poorly designed user interface riddled with functionality problems.

According to Landauer (1995) the average software program has 40 design flaws that impair employees' ability to use it. The cost in lost productivity is up to 720%.

Reduced errors.

If the interface is consistent, unambiguous and caters to user expectations in terms of the sequence and structure of tasks, then the user error rate will fall dramatically. This will help increase the productivity of users.

Reduced training.

If the interface is well designed this can help encourage learning, thereby reducing training time and effort. According to Karat, "organizations that ensure their employees are provided with easy-to-use products see dramatic reductions in training time and, subsequently, great reductions in training costs."

Reduced support costs

The Internet is the cheapest support channel you can use. Good usability should result in new and existing customers using your site to place orders, check orders, perform queries on product information and after-sales services - all at a considerably lower cost than traditional channels e.g. over the phone or in-shop.

Improves Risk Management

Design problems can be detected earlier in the development process through usability testing with actual users, long before coding begins.

Furthermore, an early definition of user goals and usability objectives can also help reduce the development process and save both time and money. The value of usability in improving the quality of systems is confirmed by a survey by Keil and Carmel (1995), which showed that the probability of project success is improved by user centered design.

Reduced development costs

Usability can help to eliminate wasted development time by focusing on the functionality required to meet the needs of real users. Design problems can be detected early in the development process. This, in turn, results in fewer code revisions, saving both time and money.

• Proof that your designs work - actual users validate your designs long before they are built, so you know the designs will work
• No more 'last minute' changes - designs are tested and completed before coding begins, so no more last minute panic to implement changes
• Provides accurate picture of how users work - no more guessing how users might use the interface: you know before you start and can code accordingly.

About the author
	Gul Amir Khan is the Chief Usability Consultant for MicroUsability and the current President of the Usability Professional's Association (Singapore Chapter). Gul has been trained in Game Theory and Strategic Behavior Analysis and has incorporated these techniques in web usability engineering. He has conducted numerous usability projects and usability workshops across Asia.