Software Engineers: This One Outdated Coding Habit Could Tank Your Next Job Interview

1. Let Me Tell You a Quick Story...

A buddy of mine — super sharp guy, 10 years in the game — recently bombed a job interview. Not because he didn’t know how to code. Not because he lacked experience. But because he used… wait for it… an outdated coding habit that instantly turned off the interviewers.

You know what it was?

He still wrote everything like it was 2005.

Hungarian notation, overly verbose loops, avoiding newer language features — all that stuff.

Look, I get it. We all have muscle memory. We’ve all got habits from the early days of learning to code. But here’s the thing: interviews are part skill test, part vibe check. And if your code feels dated, it sends the wrong signal, especially to younger engineers or teams that are trying to stay modern.

2. So What’s The Habit That Could Sink You?

Writing old-school, overly verbose loops instead of using clean, modern constructs.

Let’s break it down.

Instead of this:

cpp
for (int i = 0; i < data.size(); i++) {
    cout << data[i] << endl;
}

Use this:

cpp
for (const auto& item : data) {
    cout << item << endl;
}

Or if you’re in Python, instead of:

python
i = 0
while i < len(my_list):
    print(my_list[i])
    i += 1

Try this:

python
for item in my_list:
    print(item)

It’s not just about style — it’s about clarity, intent, and readability.

3. Why This Actually Matters in Interviews

Imagine you're the interviewer. You're skimming through a shared code editor during a live session. You’ve got 45 minutes to assess this person.

The moment you see someone using dated patterns, your brain goes:
"Hmm… are they up-to-date with modern practices?"
And honestly, it’s not always fair. But it happens.

For junior devs, it can come off like you haven’t studied newer patterns. For senior folks, it can look like you’re stuck in your ways or haven’t kept up with evolving standards.

And if you're a hiring manager without a dev background? You’re probably relying on feedback from more modern-minded team members, who might quietly raise a flag after seeing your old-school code.

4. "But My Code Works Just Fine!" – Yeah, But…

Sure, it compiles. It runs. That’s not the point.

Modern code isn’t just about getting the job done. It’s about writing for other humans — your future teammates. It’s about communicating intent, not just logic.

That’s what good interview code should do.

And let’s be real — in a high-pressure interview, your code is a window into how you think. It’s like showing your work in math class. If your thinking looks ancient, it feels like a red flag.

5. What You Can Do Right Now

Here’s a quick checklist you can use to modernize your coding habits today:

✅ Learn and practice modern loop syntax in your preferred language
✅ Use built-in functions and iterators where possible (like map, filter, forEach)
✅ Ditch outdated practices like manual counters unless explicitly required
✅ Read open-source code from active projects to see what’s current
✅ Ask peers for feedback on your interview code style

And if you’re prepping for interviews:

Practice in an environment like LeetCode or CodeSignal using modern syntax only
Watch mock interviews on YouTube with commentary — they often point this stuff out

6. For Interviewers: What This Tells You

If you're on the other side of the table, pay attention when a candidate uses legacy patterns.

It doesn't mean they're a bad dev. It might just mean they haven't had time to refresh. So dig a little deeper.

Ask: “Why did you choose that pattern?”
See if they can write modern code — sometimes nerves get in the way
Consider the context — maybe their last job required legacy support
Evaluate whether their habits are fixable through mentorship

Outdated habits aren’t dealbreakers by default. But they can hint at how much effort someone puts into staying current.

7. Final Thoughts: The Devil’s in the Details

You don’t need to use the flashiest syntax or the most bleeding-edge language features to impress in an interview. But you do need to show that you care about clean, modern code.

So take a minute and look at your go-to patterns. Are they helping you… or holding you back?

Because sometimes, the one little habit you haven’t updated in years — that thing you do automatically without thinking — could quietly tank an interview before it even gets going.

And you deserve better than that.