Debounce vs throttle

A production symptom appears first: flaky tests, stale state, slow UI, late cleanup, or growing memory. Use debounce for search boxes and validation; use throttle for scroll, resize, and pointer tracking.

Calling an API for every keypress or using throttle where the final value matters most.

Fix the root scheduling, cleanup, or concurrency pattern instead of adding arbitrary waits.

try {
  await operation();
} finally {
  cleanup();
}

The console lane proves the visible order: search: js . The active line and queues show why source order changed.

Reproduce the symptom with a small test, apply the safer pattern, then verify the flaky, slow, or leaking behavior disappears.