❌ 10 Mistakes I Made in React (And How to Avoid Them in 2025)

🧠 Intro: Learn From My Pain

I’ve been working with React for years from personal side projects to complex production apps.

Along the way, I made some painful mistakes that cost time, performance, and sanity. In 2025, the React ecosystem has matured but these mistakes still happen daily.

So here’s a list of the top 10 mistakes I made, and how you can avoid them.

⚠️ 1. Ignoring Component Re-renders

The mistake: Assuming React will “just optimize everything.”

What happened: My components re-rendered even when props hadn’t changed, causing lag and jank.

Fix: Use tools like:

• React.memo for pure components
• useMemo and useCallback where needed
• Why Did You Render to detect unnecessary renders

⚠️ 2. Overusing useEffect for Everything

The mistake:

Using useEffect to fetch data, update state, and even set flags, all in one component.

Fix:

• Don’t use useEffect for derived state, compute it directly
• Prefer declarative patterns (like react-query, zustand, or swr)
• Use useEffect only when you need side-effects (API calls, subscriptions)

⚠️ 3. Not Using a State Manager Early Enough

The mistake: Passing props deeply and lifting state too much.

Fix:

• Start with useContext for light state sharing
• Upgrade to Zustand, Redux Toolkit, or Jotai for medium-large apps
• Keep local UI state (open, hovered) in components

⚠️ 4. Writing Huge Components

The mistake: One component = 500+ lines = nightmare.

Fix:

• Follow the single-responsibility principle
• Split UI → logic → styles
• Use custom hooks to move logic out (useTodoFilters, useFetchPosts, etc.)

⚠️ 5. No Folder Structure or Consistency

The mistake: Files were dumped into /components and /utils with no naming rules.

Fix:

• Use a scalable folder structure (by feature, not type)
• Adopt a naming convention (Button.tsx, useUserStore.ts)
• Add barrel exports (index.ts) where it makes sense

⚠️ 6. Forgetting to Handle Loading & Error States

The mistake: Only showing the happy path. No spinners, no retries, no fallbacks.

Fix:

• Always show loading UI (Skeleton, Spinner)
• Handle errors with UI fallbacks (ErrorBoundary, toast notifications)
• Use libraries like react-query that support isLoading, isError, etc.

⚠️ 7. Using any Too Often in TypeScript

The mistake: Using any to silence errors. Guess what? Errors came back worse.

Fix:

• Use unknown instead of any
• Leverage utility types: Partial<T>, Pick<T, K>, etc.
• Define API response types clearly (zod, io-ts, etc.)

⚠️ 8. Not Lazy Loading Routes or Components

The mistake: Everything bundled in the main JS file → slow first load.

Fix:

• Use React.lazy and Suspense
• Lazy load heavy routes and components (Charts, Editor, Maps)
• Use code-splitting wisely

⚠️ 9. Not Using a Component Library or Design System

The mistake: Rewriting buttons, modals, forms — for every project.

Fix:

• Adopt a design system (ShadCN, Radix, Chakra, etc.)
• Customize theme + tokens
• Speed up development with consistent UI

⚠️ 10. Not Reading the React Docs Often Enough

The mistake: Learning React once, then never updating my knowledge.

Fix:

• React Docs (beta.reactjs.org) are now interactive, modern, and amazing
• Follow React 19 updates (like React Compiler, Actions, etc.)
• Stay active on GitHub discussions, RFCs, and React Conf talks

💡 Final Thoughts

Every React dev makes mistakes. The key is learning from them and evolving with the ecosystem.

In 2025, React is cleaner and smarter than ever but only if you write code that plays to its strengths.

🙌 Hope this list helps you avoid some of the traps I fell into.

Let me know which mistake you’ve made — or what you'd add to this list 👇

If you're struggling with any of the React mistakes above — or want guidance on scaling your frontend project — I offer 1:1 consultations here:

👉 Book a session with me

Let’s solve your frontend problems together.