Personality is by itself a powerful way to engage your audience. It helps people understand who you are and shapes how they interact with you, while setting the tone for the voice, aesthetic, and interaction design of your site.
Surprise is the application of such emotional design in what Aaron Walter calls "a concrete interaction pattern".
Have you ever noticed that hearing your favourite song on the radio seems so much more enjoyable that when you play it yourself? A moment of surprise compresses emotion into a split second, making our reaction more intense and creating a strong imprint on our memory. So we remember it. Obviously surprise is an immediate reaction by the human brain, but that delight lasts within your memory for...well, ages.
Moreover, surprise elicits a gut reaction. surprise that triggers the right gut reaction bypasses cerebral judgements that might prevent users from clicking, signing up for a service, or buying. It's not about being deceitful, which is where some of the blackhat negative options come from PET. It's about building positive perceptions.
And here's the great example Aaron gives us: Photojojo http://photojojo.com) — a website devoted to making digital photography more fun—weaves surprise into their ecommerce experience. As the web has matured, ecommerce interaction design has become very standardised because it makes the purchase process easier for people to learn and remember. This is the safe option.
Here are some examples how Photojojo.com uses surprise and delight to entertain: 1. Atop each Photojojo product page perches a shopping cart with a real personality. He’s gray and sullen, though at first we don’t know why. The mystery is solved when the customer clicks the “add to cart” button, sending an item arcing across the page into the cart. The poor soul promptly turns green and smiles in delight. 2. A mysterious lever sits between the “add to cart” button and the main product image that says "do not pull". Those that pull the lever are startled as an orange, muppet-like arm descends onto the page, yanking it upward to reveal the product description, which lies below the proverbial page fold. The sheer fact that this lever has a negative association to it "do NOT pull" suggests disruption against the status quo. Note: there are more as indicated by Amit Gupta.
"Emotional design is part of our marketing strategy. People tell their friends about the bubble that hops up to the top of the page when you add something to the cart, they tell their Twitter followers and blog readers about the “Do Not Pull” lever on our product pages, they mention how much they love the sandwich and dinosaur on our contact page when they email us, and they upload photos of their invoice to their Flickr accounts."
The result of these interactions? Well, according to Amit Gupta, a distinct increase in conversion rates. No doubt, too, brand efficacy and loyalty prevails with this humorous and delightful technique.