5 React Mistakes I Made (And How You Can Avoid Them)

11 min readJul 9, 2023

I remember when I started learning React at a coding bootcamp, and was very excited to try it out. But I quickly realized that React was not as easy as I thought it would be.

I struggled with the fundamentals, and I didn’t understand how to modularize my components. My code was a mess, and my applications were slow and unresponsive.

I was frustrated, but I didn’t give up. I kept learning and practicing, and eventually I started to get the hang of it. I learned how to use React’s core concepts, and I figured out how to write clean, maintainable code.

I know how you feel

As a front-end technical mentor, I’ve worked with many developers who are learning React. I’ve seen firsthand the common mistakes that people make, and I’ve helped them to overcome these challenges.

I’m writing this article to help you avoid the same mistakes that I made and that my students have made. I’ll share some of my insights on the common mistakes and challenges that people face when learning ReactJS.

I hope that this article will help you to become a better React developer. So let’s get started!

Common Mistakes

Mistake 1: Neglecting the fundamentals

When I first started learning React, I was eager to jump right in and start building cool stuff. But I quickly realized that I was making a mistake. I was trying to learn React without first mastering the fundamentals.

I didn’t understand what JSX was, or how to structure React components. I didn’t know what state and props were, or how the component lifecycle worked.

And as a result, my code was a mess. It was hard to read and understand, and it was slow and unresponsive.

I eventually realized that I needed to take a step back and learn the fundamentals of React before I could move on to more complex topics.

I started by reading the React documentation and watching tutorials. I also practiced by building simple React components.

Once I had a solid understanding of the fundamentals, I started to see a big improvement in my code. It was easier to read and understand, and it was more performant. I was also able to build more complex applications.

If you’re just starting out with React, here are a few tips for mastering the fundamentals:

Learn JSX. JSX is a syntax extension that allows you to write React components using HTML-like code. It’s a powerful tool that can help you to write more concise and readable code.
Understand state and props. State and props are two of the most important concepts in React. State is the data that your component needs to keep track of, and props are the data that your component receives from its parent component.
Grasp the component lifecycle. The component lifecycle is a series of events that occur when a React component is created, updated, and destroyed. Understanding the component lifecycle will help you to write more efficient and reusable code.

There are a few resources that can help you to overcome the challenge of mastering the React fundamentals:

The React documentation. The React documentation is a great resource for learning about the fundamentals of React. It’s well-written and easy to follow.
React tutorials. There are tons of React tutorials and resources available online. These tutorials can help you to learn the fundamentals of React by example. I personally benefited from the following tutorials and resources: Full Modern React Tutorial: Net Ninja, The Beginner’s Guide to React: Egghead.io, and React Beta Docs.
Practice. The best way to learn the fundamentals of React is to practice. Start by building simple React components, and then gradually build more complex applications.

Remember, don’t be afraid to ask for help if you get stuck. There are many online communities and forums where you can get help from other React developers.

I have personally benefited a lot from Dev’s React Community, Reddit, Reactiflux, and of course, Stack Overflow.

Mistake 2: Not utilizing React’s modular structure

As a front-end technical mentor and full-stack developer (heavy on front-end), one of the most common mistakes I see students make is not utilizing React’s modular structure.

I remember one learner who was building a simple to-do list application. He started by creating a single component that contained all of the code for the application.

Consequently, his code was very difficult to read and understand, and it was also very difficult to make changes to the application.

React’s modular structure allows you to break your application down into smaller, self-contained components. This makes your code easier to understand, maintain, and test.

There are a few things you can do to organize and structure your components in a modular way:

Use the Single Responsibility Principle (SRP). The SRP states that each component should have a single responsibility. This means that each component should only do one thing.
Extract reusable components. If you find yourself using the same code in multiple components, extract it into a reusable component. This will make your code more concise and easier to maintain.
Leverage React’s folder structure. React’s folder structure can help you to organize your components in a logical way. For example, you could create a folder for each feature of your application.

To overcome the challenge of modularizing your React components, use the following strategies:

Start small. Don’t try to modularize your entire application all at once. Start by modularizing a few components, and then gradually work your way up.
Use a linter. A linter can help you to identify potential problems with your code. This can help you to catch mistakes before they cause problems.
Get feedback from others. Ask a colleague or mentor to review your code. They may be able to identify potential problems that you have missed.

Below is an example demonstrating how to modularize a React component:

This is a simple button component. It takes a single prop, children, which is the text that will be displayed on the button. The component is exported so that it can be used in other components.

Now, let’s modularize this component. We can create a new folder called components and put the Button component in there.

We can also create a new file called index.js in the components folder and export the Button component from there.

This is how we can modularize a React component. By modularizing our components, we can make our code easier to understand, maintain, and test.

Mistake 3: Overcomplicating state management

As a front-end technical mentor, I often see budding developers make the mistake of overcomplicating state management in their React applications. This can lead to a number of problems, including:

Slow performance
Difficult to maintain code
Bugs

React provides a number of built-in tools for managing state, such as useState and useReducer. These tools are simple to use and can be very effective for managing small amounts of state.

To effectively manage state in React you should:

Use the right tool for the job. If you only need to manage a small amount of state, use useState. If you need to manage more complex state, use useReducer.
Keep your state as simple as possible. The more complex your state, the more difficult it will be to manage.
Use functional components. Functional components are easier to test and maintain than class components.
Use the shouldComponentUpdate lifecycle method. This method allows you to prevent your component from re-rendering unnecessarily.

The best way to overcome the challenge of overcomplicating state management is to start simple. Use the useState hook to manage small amounts of state, and only use more complex tools when necessary.

Here is an example of how to use the useState hook to manage state:

This code creates a simple counter that increments every time the button is clicked. The useState hook creates two variables: count and setCount.

The count variable stores the current value of the counter, and the setCount function is used to update the value of the counter.

The handleClick function is called when the button is clicked. This function calls the setCount function to increment the value of the counter. The setCount function takes a new value for the counter as its argument.

The useState hook is a simple and effective way to manage state in React applications. It is easy to use and can be used to manage small amounts of state.

Mistake 4: Ignoring performance optimizations

I remember when I first launched my React application, I was so excited to see it in action.

But my excitement quickly turned to disappointment when I saw how sluggish it was. It took forever to load, and even then, it was slow to respond to user input.

I was baffled. I had followed all the best practices for writing React code, so why was my application so slow?

After some debugging, I realized that I had been making a critical mistake: I was ignoring performance optimizations. I was rendering my components unnecessarily, and I wasn’t using any tools to lazy load or split my code.

Once I started optimizing my application’s performance, it made a huge difference. It loaded much faster, and it was much more responsive to user input.

Performance is an important consideration for any web application, but it’s especially important for React applications.

React applications are often used for interactive, real-time applications, so even a small performance improvement can make a big difference.

There are a number of things you can do to optimize the performance of your React application, including:

Identifying and mitigating unnecessary re-renders. When you render a component, React will re-render all of its child components as well. This can lead to performance problems if you’re rendering components unnecessarily.
Implementing code splitting and lazy loading. Code splitting allows you to load different parts of your application’s code on demand. This can help to improve performance by reducing the amount of code that needs to be loaded initially.
Using React.memo and shouldComponentUpdate. These React hooks can help you to prevent unnecessary re-renders by only rendering a component when its props or state have changed.

Here are some tips for improving the performance of your React app:

Use a profiler to identify performance bottlenecks. There are a number of tools you can use to profile your React app, such as React DevTools and the Chrome Profiler. These tools can help you to identify the parts of your app that are causing performance problems.
Use a performance budget. A performance budget is a way of setting limits on how much resources your app can use. This can help you to ensure that your app is always performing within acceptable limits.
Use performance-optimized libraries and tools. There are a number of libraries and tools that can help you to improve the performance of your React app. For example, you can use the React Performance Toolkit to help you to identify and fix performance problems.

Optimizing the performance of your React app can be a challenge, but it’s worth it. By following the strategies above, you can make your app faster and more responsive, which will improve the user experience.

Here are some tips on how you can improve the performance of your React app:

Use React.memo to prevent unnecessary re-renders. For example, if you have a component that renders a list of items, you can use React.memo to prevent the component from re-rendering when the list of items changes.
Use shouldComponentUpdate to control when your component re-renders. For example, you can use shouldComponentUpdate to prevent your component from re-rendering when the props that it receives haven’t changed.
Use code splitting and lazy loading to load your app’s code on demand. This can help to improve performance by reducing the amount of code that needs to be loaded initially.

The snippets below illustrate the mistake of ignoring performance optimizations and demonstrate how it can be avoided:

Mistake 5: Neglecting code maintainability and readability

When we first start building React applications, we are eager to get started and see our ideas come to life, so we don’t spend much time thinking about the long-term maintainability of our code.

As a result, our code quickly becomes a mess. Like me, most of you have had long, unwieldy functions, and components that are tightly coupled. It makes it difficult to understand how our code worked, and even harder to make changes.

Clean and maintainable code is important for a number of reasons. First, it makes your code easier to understand. This is important for yourself, as well as for anyone else who needs to work on your code in the future.

Second, clean and maintainable code is easier to change. If you need to make a change to your code, you’ll be able to do it more quickly and easily if your code is well-organized.

Third, clean and maintainable code is more performant. When your code is easy to read and understand, it’s easier to optimize for performance.

Here are some tips for writing clean React code:

Use consistent and meaningful naming conventions. This will make your code easier to read and understand.
Apply modular CSS methodologies. This will help you to keep your CSS code organized and maintainable.
Utilize code linting and formatting tools. These tools can help you to catch errors and improve the readability of your code.

There are a few things you can do to overcome the challenge of writing clean and maintainable React code:

Start small. When you’re first starting out, focus on writing small, well-organized components.
Get feedback. Ask other developers to review your code and give you feedback.
Use a linter. A linter is a tool that can help you to catch errors and improve the readability of your code.

The code snippet below demonstrates how to improve the readability of a React component:

The original code is difficult to read because it has a lot of nested elements. The improved code, on the other hand, is easier to read because it uses a functional component and it separates the presentational logic from the state management logic.

Conclusion

In this article, I’ve shared my journey as a React developer and the common mistakes I’ve made along the way. I hope that by sharing my experiences, I can help you avoid making the same mistakes.

Here are the key takeaways from this article:

Understand the fundamentals of React. This includes learning JSX, state, props, and the component lifecycle.
Modularize your React components. This will make your code easier to understand, maintain, and test.
Simplify state management. Use local component state for simple cases, React Context for global state, and Redux for more complex scenarios.
Optimize your React applications for performance. Identify and mitigate unnecessary re-renders, implement code splitting and lazy loading, and use React.memo and shouldComponentUpdate.
Write clean and maintainable React code. Use consistent naming conventions, apply modular CSS methodologies, and utilize code linting and formatting tools.

I’ve also included a number of resources throughout the article that you can use to learn more about React.

I hope you found this article helpful. If you have any questions, please feel free to leave a comment below.

Learning React can be challenging, but it’s also very rewarding. By following the tips in this article, you can avoid common mistakes and become an excellent React developer.

So what are you waiting for? Start learning React today!