Performance Optimization: Perceived vs Actual Latency

Overview

Perceived latency is more important than actual latency. A 3-second operation that feels instant is better than a 1-second operation that feels slow. This skill teaches you to optimize how fast your interface feels, not just how fast it actually is.

Core Principle: The Linear Method

The "Linear Method" popularized by Linear.com prioritizes a steady cadence of quality over frantic sprints. Applied to performance, this means:

Speed is a feature, but perceived speed is the ultimate UX.

When a user creates a task, the UI should show it as created instantly. The network request happens in the background. If it fails, the UI gracefully rolls back. This pattern builds trust—users know the system will handle the details.

Actual vs Perceived Latency

Actual Latency

The real time it takes for an operation to complete (measured in milliseconds).