5 JavaScript Mistakes I Made as a Beginner (and How to Fix them)

ofodilechiemerie78-glitch — Wed, 11 Nov 2026 08:07:50 +0000

When I started learning JavaScript, I broke things constantly. Looking back, the same five mistakes caused most of my headaches. Here they are, with the fixes.

Using var everywhere. I didn't understand that var is function-scoped, so variables leaked out of loops and blocks and caused strange bugs. Fix: use let for values that change and const for everything else.
Confusing == with ===. Loose equality converts types silently, so "5" == 5 returned true. Fix: default to strict equality (===) and compare values of the same type.
Losing track of this. Inside regular functions, this changed depending on how the function was called, and my callbacks broke. Fix: use arrow functions for callbacks, which inherit this from the surrounding code.
Messy event listeners. I attached listeners inside loops and functions without removing them, so one click fired multiple times. Fix: add listeners once, remove them with removeEventListener when finished, or use event delegation on a parent element.
Ignoring asynchronous code. I expected fetch() to return data immediately and got undefined or a pending Promise instead. Fix: use async/await, wrap calls in try/catch, and remember that code after an await only runs once the result arrives. Every one of these mistakes taught me something that no tutorial could. Bugs are not proof that you're bad at coding; they're the fastest way to learn how the language really works. When something breaks, slow down, read the error message, and use console.log or the debugger to trace what's happening. Then keep building.

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5 JavaScript Mistakes I Made as a Beginner (and How to Fix them)