Memorizing without understanding, coding silently (not thinking aloud), not handling edge cases, confusing debounce and throttle, not understanding the event loop, and not knowing this binding rules.

Because interviewers often tweak the question. If you memorized a specific implementation, you cannot adapt. Understand the concept, implement from scratch, and be able to modify it. Understanding > memorization.

Debounce: delay until activity stops (e.g., search input). Throttle: limit to once per interval (e.g., scroll handler). Practice implementing both from scratch. Know the use cases for each.