2011 alum Russ Maschmeyer explains to FastCoDesign:
The design goal was to marry the idea of a page title and a search field to create a unique, almost magical page title where you could describe something you wanted to see and it would appear below," says Russ Maschmeyer, the lead designer on the product. Maschmeyer hoped to reduce the visual noise that would come with a high-contrast white box and a prevalent search button. "It looked wonderful and sounded great on paper," he says, "but in reality it led to a lot of confusion for our users. And so: Maschmeyer and his team began testing new designs to target that problem. In one test, they changed just the color of the search box for a small percentage of users. The white search box performed more than twice as well as the next best solution, a darker tone of blue than Facebook’s blue background. After making this discovery, the team tested smaller tweaks, such as adding a permanent search icon to the search box, a written prompt, and the position of other icons.
Nicely done. Take a look for yourself.
