Bell Labs engineer John Karlin helped pioneer the use of behavioral testing in industrial design. His New York Times obituary offers this nugget:
Mr. Karlin also introduced the white dot inside each finger hole that was a fixture of rotary phones in later years. After the phone was redesigned at midcentury, with the letters and numbers moved outside the finger holes, users, to AT&T’s bewilderment, could no longer dial as quickly.
With blank space at the center of the holes, Mr. Karlin found, callers no longer had a target at which to aim their fingers. The dot restored the speed.
Karlin, the Times reports, “stud[ied] the psychological capabilities and limitations of ordinary people” to identify telephone designs that maximized usability.
Cara Harshman explains a test the Romney campaign ran:
The team started optimizing for donations with a test on the main call-to-action in the right upper corner of the homepage. They wanted to see whether button color – blue, green, yellow or red – and word choice – “Contribute,” “Support”, or “Donate” – impacted the likelihood of a visitor to click.
Overall they found that color did not have a definitive impact, but the word “Contribute” did show a statistically significant improvement of 10%.
The color of the button has little to no effect on it’s own. What is more important is how it changes the visual hierarchy of the whole page, how it makes the call-to-action stand out. Plus additional information and wording of the button itself.
It’s also what we’re used to. Bing increased their revenue by $80 million dollars by finding the exact color of blue for their links. Why is that? It’s because people are used to links being blue.
Erik Runyon compiles some actual data on how people use carousels, including auto-forwarding carousels and those requiring users to click through. His conclusions:
First, if they’re going to insist on a carousel, they need to include compelling content that not only entices users to click, but can get their attention in the first place. Second, I might suggest keeping the number of features to a maximum of four (or better yet, three), as it appears that as the number of features increases, the click-throughs on sub-features decreases dramatically. Finally, I’d suggest that the subject matter can make a big difference.
Most website carousels are added not because of a focus on the consumer but because of internal organizational politics, Brad Frost points out. His first rule for when to add a carousel: “Make sure you actually need one.”
Meghan Keaney Anderson warns against personalizing content just because you can: “Personalization without a good reason breaks the cardinal inbound rule: Marketing should be driven by the prospective customer’s needs. At its core, marketing should be useful.”