Code has two audiences: the machine that executes it and the humans who maintain it. Most education about programming focuses on the machine — correctness, performance, algorithmic efficiency. These things matter, but the human audience matters just as much, and in most business software it matters more.
The machine will execute any syntactically valid code. It does not care whether your variable names are meaningful or whether your functions are small and focused. Humans care deeply about these things, because humans have to read code to understand it before they can safely change it.
Naming as Communication
The single most impactful thing you can do to improve code readability is choose clear, descriptive names. A function called processData tells you almost nothing. A function called calculateMonthlySubscriptionCost tells you exactly what it does. Variable names like x and temp are appropriate in very short, contained contexts; everywhere else, they are an obstacle.
Good naming is hard. It requires you to understand what a thing is and articulate that understanding precisely. The difficulty is part of the value — the struggle to name something clearly often reveals that you do not yet understand it as well as you thought.
Small, Focused Functions
Functions that do one thing are easier to understand, easier to test, and easier to reuse than functions that do many things. When a function grows to the point where you need to add section comments to distinguish what each part does, it is telling you it should be broken into smaller functions.
The right size for a function is the size that makes it easy to understand what it does from its name and signature, without needing to read its implementation. This is a judgment call, but it is one that becomes easier with practice.
Comments That Add Value
Comments should explain the why, not the what. A comment that says "increment counter" next to a line that increments a counter adds nothing. A comment that says "we use a counter here instead of a boolean because we need to handle overlapping requests" adds significant context that is not visible from the code itself.
When code requires a comment to explain what it does, that is usually a signal that the code should be rewritten to be clearer. When code does something surprising or non-obvious for a legitimate reason, a comment explaining that reason is invaluable.