Last week, in our inaugural UX Principles blog post, user experience director Michael Ferguson explained the importance of forgiveness as an integral element of user experience. In this week’s post, he tackles another tenet of UX thinking: responsiveness.
When a user takes an action, the system should respond immediately. This doesn’t necessarily mean that the request (most commonly in the form of a click, a tap, a gesture, or a voice command) has to be fulfilled immediately — just that it should be acknowledged immediately.
The user needs to know what state the system is in, and the system needs to know what the interface is telling the user. When both are accurate, the input will be good. If they are inaccurate, it won’t be — as when a user repeatedly issues the same command (each time kicking off processes that further delay output).
For example, when a user removes an article from Personal Post, it disappears immediately and a message is displayed that indicates how the action will be used to improve the stream.
When you do this:
You immediately see this:
The quick response gives the user a sense of control, and shows him an important facet of how the product is personalized.
Apple’s Siri in iOS 5 sounds two quick beeps indicating she (or, in some locations, he) is listening. A user will see the microphone icon react to his voice instantly. When Siri believes the user has completed his part of the dialog, a second, higher-pitched set of beeps emits, letting users know that what they have said has been received. Then, the microphone button at the bottom of the screen animates — a convention telling users that Siri is processing the input. Siri briefly displays the translated speech, and then responds. This responsiveness walks a fine line, though: when we talk, we often pause to complete thoughts and consider wording. Siri takes that pause as a cue that users are ready to input what they have said thus far.
Users tend to adjust to system responsiveness if they feel that the value of the result outweighs the instant gratification they desire. Many users adjust to Siri’s rhythm and limitations and learn to time movements with a slight expectation of lag while playing Wii or with Xbox Kinect.
Responsiveness is visceral — noticeable at the level of thousandths of a second. To get a great sense of this, look at what Microsoft’s Applied Sciences Group is doing: they’ve prototyped a touchscreen with 1ms responsiveness time (vs. the 100ms commonly experienced by the market today.) You can feel how much a difference that makes.
For more behind-the-scenes UX tips and tricks, check back next week for the latest installment of “UX Principles.”