Why Your React App Re-renders Too Much (And How to Fix It)

Clicking a single checkbox triggered multiple re-renders across an entire React dashboard — a silent performance tax paid for months. The fix involved tracing five root causes: state living too high in the tree, inline object/array props, unstable function references, recreated context values, and un-memoized expensive components. Each cause has a targeted, profiler-guided fix that avoids over-engineering.