Importance of Doherty Threshold
What is Doherty Threshold? It states that productivity soars when a computer and its users interact at a pace less than 400 ms that ensures that neither has to wait on the other.
In fact, it was thought at one time that a relatively slow response, up to two seconds, was appropriate because the individual was thinking about the next task. Rapid response time research now shows that the evidence does not support this earlier theory: productivity increases in more than direct proportion to a decline in response time.
“What’s true is that we interact faster with systems that give us fast feedback. And remember, the transition time is part of this experience of speed.”
In 1979, IBM researchers Walter J. Doherty and Richard P. Kelisky proposed that our action plans would be disrupted by changes in device response times. As the response time of the system increases, our flow breaks and we get into the typical loop where we actually focus on the answers we get and challenge our expected sequence of action. It begins to slow down the pace of our clicks and taps.
“Doherty’s Threshold dictates that a user experience turns from painful to addictive after the system feedback time drops below 400ms.”
Doherty suspected that was happening because a user was storing the series of steps he wanted to take in his working memory. The long reaction times of the device were an interruption that made him lose his train of thought and eventually caused lower productivity.
“Progress bars help make wait times tolerable, regardless of their accuracy.”
“The animation is one way to visually engage people while loading or processing is happening in the background.”
If you still want to replace Doherty’s Threshold with magic numbers, here are some for you: Our brains finish registering 100ms of pictures. Our average time to respond is 250ms. Google’s Material Design indicates that it should take 100ms for basic animations to finish, 500ms for more complex ones.
