Incorrect dependency array in useEffect leading to infinite loops or stale state

My useEffect either never runs when expected, or runs too often—even infinitely—because of incorrectly specified dependencies or updates inside the effect.

Common mistakes: • Missing dependency array: runs on every render. • Including state updated inside effect (like count) causes self-triggering loops. • Including functions/objects not memoized recreates dependencies on each render ([turn0search0], [turn0search4], [turn0search8]). Fixes: • Use [] for one-time effects. • For state updates inside effect, use functional setter: jsx Copy code useEffect(() => setCount(prev => prev + 1), []); • Memoize callbacks via useCallback to stabilize deps. • Only include necessary state, props, or stable callbacks in dependency array.