Productivity soars when a computer and its users interact at a pace (<400 ms) that ensures that neither has to wait on the other.

Chapter 9 of Laws of UX covered the Doherty Threshold, and I found it really interesting. It focuses on the idea that system response times should be fast enough to keep users engaged—specifically within 400 milliseconds. Learning this gave me a deeper understanding of how timing and responsiveness can directly impact user satisfaction and trust.

What stood out to me most was how a well-designed UI that responds quickly can encourage users to stay and interact longer with an app or product. It made me realise that good design isn't just about visuals or features—it's also about the experience of responsiveness. If a system feels smooth and immediate, users feel more in control and are more likely to continue using it.

Another surprising insight was that making wait times too fast can actually cause problems. If transitions or loading times are rushed, users may not have enough time to process the information presented, which can lead to confusion or even distrust. This fine balance between speed and cognitive processing is something I hadn't considered before, but it makes a lot of sense.

The Doherty Threshold has shown me that timing is a critical part of the user experience. Moving forward, I'll be more mindful of how responsiveness, pacing, and even brief moments of delay can be used strategically to create a more trustworthy and satisfying experience for users.