The success of early eCommerce has made Web site availability and performance mission-critical. However, according to a recent Report from Forrester Research, Inc. (Nasdaq: FORR), customer satisfaction will require more than just site availability. Sophisticated online firms will eventually cap infrastructure spending and use the money saved to improve overall customer satisfaction because eCommerce sites will soon reach a point of diminishing returns.

“Based on average transaction rates and dollar amounts, Forrester believes that most companies should target 99.9% availability for their Web sites because there is little point in investing more funds in infrastructure than the site returns in revenue,” said Joseph L. Butt, Jr., senior analyst at Forrester. “Success is defined by the quality of the overall customer experience before, during, and after a transaction — what Forrester calls quality of experience, or QoE.”

Prior to transacting, companies should apply load and usability testing to their site design to improve a visitor’s experience. In addition to focus groups, rigorous Web site reviews, and usability-lab studies, firms that improve design and navigation functions will boost end user satisfaction. Companies must provide shoppers with intuitive navigation and make it easy for returning customers to purchase quickly.

Speed and efficiency are also critical during transactions to keep both servers and customers fulfilled. A firm’s ability to check inventory for availability and to track orders through delivery can improve the customer experience significantly. A positive consumer experience is also based upon merchandise delivered on time, which requires end-to-end logistics that provide service continuity from purchase to delivery.

After a transaction, companies must layer people and business incentives on top of technology to maximize online customer retention. Customer service initiatives, including quality personal attention, coupons, or special discounts, also make up for inconveniences caused by technology.

“Although Internet companies today garner high valuations due to the large number of Internet buyers, market share will eventually diminish,” added Butt. “Acquiring new customers in 2004 will require millions. The best bet for online companies is to dazzle customers with a quality shopping experience now — before it’s too late.”

For the Report “Is Nonstop Enough?” Forrester interviewed 50 companies with transactional Web sites: 40 eCommerce sites, five content sites, and five financial sites. On average, firms reported uptime of about 98%.