What you need to know
Memoization adds comparison and dependency complexity. It helps when a calculation or child render is measurably costly and its inputs remain stable, not simply because a page contains many components.
How to apply it
Profile the slow interaction, optimize the part that consumes time, and verify the improvement after the change. Keep dependencies accurate and prefer simpler data structures when they solve the cause.
Common mistake to avoid
Do not wrap every function and value in memo hooks. Premature memoization can make code harder to read without improving a real bottleneck.