Usability and the happy shopper

It’s a cliché of our discipline; a usable e-commerce site generates more sales. Web analytics show measurable differences in consumer behaviour following design changes. The idea is now sufficiently established that “good experience” is widely seen not so much as a market differentiator but as a hygiene factor, a fundamental tool to deliver a sales and marketing strategy.

Let’s tease this idea apart to identify why good design drives sales and how we can exploit the usability toolkit to get it right. We need to look at how people shop, the limits on economic rationality and the web as a social medium.

How shopping works

A simple task model

1. Discover a product
   1. Become aware of a product
   2. Find information about the product
   3. Assess personal relevance of the product
2. Select model
   1. Identify alternative models of the product
   2. Identify alternative suppliers of the product
   3. Assess and compare
   4. Select a model
3. Select a channel
   1. Identify alternative channels for product
   2. Assess and compare
   3. Select a channel
4. Buy
   1. Find the product
   2. Manage basket
   3. Specify delivery
   4. Pay

This model includes cognitive, social and practical steps; each step represents a risk of failure. Customers can only buy products they have heard about. They need to understand what a product does and how it could enhance their lives. They look for an outlet that is trustworthy, affordable and convenient.

What shoppers need

Within this task model, there are some important user goals:

• finding;
• discovering;
• understanding;
• assessing;
• comparing;
• choosing; and
• administering.

Finding means locating information that you know is there. You find a number in the phone book. Discovery is more subtle. It reveals information that you need – but don’t know that you need. For example, you might discover an attractive new variety of hybrid Rose while browsing your garden centre for a watering can. Finding and discovery are goals of Information Architecture. The more complex the product set, the greater the need to focus on “findability”.

Understanding, assessing, comparing and choosing work together. They enable a customer to make a decision about trying something new. Adoption is an intellectual process, a social process and an emotional process. According to Everett Rogers’ influential Diffusion of innovation, potential customers seek information to reduce uncertainty and assess “relative advantage”. Well written content quickly answers the tough question, “What’s in it for me?” Consistent coverage and layout make it easy to compare alternatives. Clear and influential content is the goal of copywriting and information design.

Administering is a chore; where should it be delivered? how do you want to pay? Good software ergonomics ensure that this data entry is efficient and simple. This is good old-fashioned usability at work.

Bounded rationality

Economists generally assume that buyers act rationally, seeking to minimize their costs and maximize their returns. Shoppers seek information and compare alternatives in order to make sound economic decisions. Herbert Simon refined this model: “maximisers” keep researching till they find the perfect product; “satisficers”, on the other hand, stop when they find a product that is good enough. In either case, well-written and trustworthy information is essential to discourage defection to another site.

Trust

Shopping is a social act. A well-crafted design suggests a professionally-run business. Direct, personal language implies plain dealing. Editorial content can demonstrate interest and expertise. User-generated content adds credibility and social “buzz”. Plain English says, “we don’t need to hide behind the small print.” Explicit privacy and security policies tackle distrust of online payment. Attractive presentation and engaging writing create a sense of well-being that can transfer to a positive view of the products on display.

Designing for a good shopping experience

An effective design actively addresses the needs of shoppers. Here are some examples.

Discovering	The catalog reflects the way customers understand and use products. It avoids the “house” taxonomies of manufacturing and marketing. It uses carefully managed see-also links to identify genuine alternatives.
Finding
Understanding	Product descriptions are clear, complete, consistent and easy to read. Technical terms are explained. Potential uncertainties are recognised and addressed.
Assessing	Product descriptions explain relevant benefits in a direct, concise style. They avoid marketing clichés and adopt a direct, personal style, consistent with the values of potential buyers.
Administration	Payment and delivery dialogs exploit sensible defaults, remember preferences and tightly integrate payment engines to eliminate repeated data entry.

A good shopping experience

“I came across Kopi coffee on the coffeemajic site. It’s the world’s most expensive coffee, made from beans ‘predigested’ by a civet. Because it sounded fascinating and vile in equal measure, I sought out buyer reviews on the company’s community board and read about the personal experiences of the chief taster. That was enough background for me; I convinced myself I had to try it. I used the product list to compare the price and flavour of different brands and quickly settled on one variety to check out.

I thought about picking up a packet at my local deli. However, because the site remembers my details, it was just faster to buy it there and then.”