Criteria for optimal web design (designing for usability)

By Michael L Bernard

Only a small percentage of people actually purchase merchandise online. In fact, the percentage of people that actually buy online is approximately 3 to 5 percent (Slatalla, 2001). There are several reasons for this:

First, shoppers often do not feel secure in purchasing products online. According to a study by Tilson, et al. (1998), participants indicated from a list of 40 items that credit card security is the most important deterrent for them to buy online. (The other top deterrents were easy return/exchange methods, detailed descriptions of items, price, secure personal information, pictures of merchandise, and simple to search, respectively). Obviously, using a secure web server to collect customer data (and communicating that it is secure) promotes the feeling of security. It is also the standard for conducting business online. Moreover, Tilson et al. further suggests providing a privacy policy on every page and highlight this policy before customers are expected to give personal information. Other suggestions are to explain the benefits from sharing personal information, provide mechanisms for controlling how this information is used, and provide a background on the company.  

Second, is a lack of specific information related to the product and store. Since online shoppers cannot physically interact with the product itself, potential customers generally require more extensive information about the product - in the form of links to detailed pictures or descriptions of the product. However, according to Spiller and Lohse (1998), over 50% of the e-commerce sites that they studied had less than three lines of text describing the products. It is argued by Lohse and Spiller (1998) that e-commerce sites should take advantage of the interactivity of the web and "offer hyperlinks to more extensive product information such as product testimonials (book reviews at www.amazon.com) and product demonstrations (software downloads)" (p. 82). 

For example, according to a survey by PricewaterhouseCooper (2001), providing more detailed information about the products can significantly increase the likelihood of the purchase being made (see Figure 1 below). 

Figure 1. Features most likely to increase the likelihood of online purchase

 
Moreover, many online stores also do not provide information related to the site itself. In fact, Spiller and Lohse found from the surveyed e-commerce sites that 95% did not have links to related products on the same site and only 25% had a help link to product-size selection. In addition, only 9% of the sites had a FAQ section, even though it has been shown that online stores with a FAQ section generally have more visits that those without them (Spiller & Lohse, 1998). The survey also found that 47% of the sites did not have an email link. This is a vital (perhaps only) way for customers and potential customer to interact with the store. It is essential to provide ways to promote customer/store interactions in order to reduce the physical and psychological separation between the customer and the store.

Furthermore, in a review of past studies Jarvenpaa and Todd (1997) gave recommendations for presenting online product information:

1. Offer discounts, except for unique products.
    

2. Focus on products that have low delivery costs.
    

3. Benchmark the e-store against traditional retail stores and catalog stores.
    

4. Emphasize brand name products and product quality.
    

5. Reduce shopping effort by providing search techniques.
    

6. Respond promptly to questions.
    

7. Provide no-cost/no-hassle return policy.
    

8. Provide rich product descriptions including images and words.
    

9. Emphasize security measures.
    

10. Provide customer testimonial.

 
Lastly, many online stores do not provide adequate service information. That is, in the e-commerce websites studied by Lohse and Spiller (1998), close to one-third did not provide company policies, background, or history. Moreover, most of the sites that did provide information provided less than 10 lines of text. 

Third, shoppers must feel comfortable in viewing the shopping items before buying. As with any store, shoppers should feel free to examine the merchandise without having to give out personal information before committing to buy. In other words, placing items into a shopping cart should be effortless and anonymous. This will allow them to feel at ease and safe while shopping online. Not doing this can have dire consequences. For example, in a study of e-commerce sites, Chaparro, Childs, Praheswari, & Rappard (Winter/2000) found that sites requiring the users to register with the site before adding items to a shopping cart deterred them from adding items to the cart. It also had the effect of producing a low amount of satisfaction with the site. 

Conversely, a well designed shopping interface can promote the shopping experience (see Dack.com (1999) for a nice overview of shopping carts and checkout interfaces. Other studies such as by Rohn (1998) provide further information pertaining to e-commerce usability dos and don'ts). 

Fourth, websites should be 'credible' to the shoppers. Fogg, et al. (2001), conducted a study that surveyed over 1,400 participants and found two elements that affected the credibility of a site: commercial implications and amateurism. The items that most negatively affected the commercial implication of sites were ones that: 

• makes it hard to distinguish ads for content

• automatically pops up new window with ads

• has one or more ads on each page

• sites that require a paid subscription to gain access.

Importantly, the item site makes it hard to distinguish ads from content received the lowest score in the entire study, and thus it is recommended to make that distinction within a site.

For the amateurism scale, sites that:

• are rarely updated with new content

• has a  link to a site that is perceived as "not credible"

• has a link that doesn't work," is "sometimes unexpectedly unavailable"

• has has a "typographical error" 

were considered the most amateurish, respectively. Sites that have been: 

• updated since your last visit

• offers information in more than one language 

were considered to be more professional. Other items that had a positive effect on website credibility were sites that: 

• provide a quick response to your customer service questions

• lets you search past content

• looks professionally designed

• send emails confirming transactions you make

From their results Fogg et al. (2001) made several credibility promoting recommendations:

1. Include elements that highlight the brick-and-mortar nature of the organization it represents, such as listing a physical address.
     

2. Make the site easy to use.
    

3. Convey expertise, such as including credentials, citations, and references.
    

4. Convey trustworthiness by stating a policy on content, etc.
    

5. Tailor the site to the visitor and acknowledging their presence.
     

6. Avoid overly commercial elements on a website (see above).
     

7. Avoid amateurism (see above).

The use of pictures may increase user trust for e-commerce websites. According to research by Steinbruck, Schaumburg, Duda, and Kruger (2002), the inclusion of a photograph for an e-bank website significantly increased the perceived trustworthiness of that website. In this study, the condition that had the highest trustworthiness ratings was for a website with a welcome page that contained a picture of a person that was identified as a customer service agent. The second highest rating was for the picture only, and the lowest rating was for a welcome page without any picture. Moreover, a study by Riegelsberger and Sasse (2002) did find that photographs increased the relationship with the brand for some individuals, but as a whole, reactions varied greatly to the use of photographs.

 

References

Software Usability Research Lab
Dept of Psychology
Wichita State University
Wichita, KS 67260-0034

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