80-hour weeks don’t make a great engineer. They’ll break a great engineer.

I’m not exaggerating when I say I was shocked by a question about working hours that I got during a recent office hour live stream. “So I heard from a developer that he would code and learn for like 80 hours a week when he started in order to be come an amazing engineer. I can barely do 8 hours a day and I want to be an amazing engineer. Advice on that?”

Here’s the TL;DR: Working 80 hours a week is neither healthy nor effective. I’d go as far as to saying it’s impossible. Sitting in front of a screen for 80 hours? Yeah, maybe, if that’s your thing. But doing actual work for 80 hours? You might very well be fooling yourself, but you’re not fooling me.

More negative side effects than benefits

Now, before we get into how many hours of work per week you really should invest into your growth, let’s first consider the side effects of spending 80 hours per week working. That is 16 hours every weekday or more than 11 hours every single day, working on your engineering career. Even if we count necessities like eating and pooping as part of work time, it’ll still leave only between 8 and 12 hours per day for the non-work parts of your life. Parts like, you know, hobbies, social life and sleep.

And it’s scientifically proven that for most people, any amount of sleep below 7 hours a night is not enough. The body needs time to recover physically and mentally. In other words, if you sacrifice sleep for other things for more than a very short time, you’re going to ruin your health. Let’s see how not only your career but your whole life flourishes while you’re dealing with the consequences of burnout (or falling asleep driving your car).

Way to sabotage yourself

Total work time also has severely diminishing returns. In other words, putting in more and more time will yield less and less additional results. Effective work requires effective rest. Why do you think Ford and his fellow industrialists themselves introduced the 40-hour work week? And that was just about physical work. Every athlete knows that muscle growth doesn’t benefit from endless training. There needs to be downtime during which the body can recuperate and grow to meet demand.

For our brain, it’s similar, but it’s even more limited in how long it can work at high performance. For knowledge workers, an 8-hour day is like a 16-hour day for the industrial laborer. It’s just not possible to keep your focus for that long, not only because people keep interrupting you, but also for physiological reasons. The brain needs time and rest to build new tissue such as the myelin that grows around neurons.

It’s not about the working hours at all

There’s also the aspect of how much you can even achieve on your own. There’s that story of someone who shipwrecked on an island with just a chess board, and ten years later returned as a grand master. That’s bullshit, because you need other people to beat the Dunning/Kruger effect, i.e. you don’t know what you don’t know. The only way to find the solutions that your brain couldn’t come up with by itself is collaboration. Grand masters learn from other grand masters, amazing engineers learn from other amazing engineers. That’s why I’m so excited about The Server Room, the community of DevOps practitioners I’m going to launch soon.

The good news is that success is not about the total time you spend working at all. Rather, it’s about how much focus time you can get in. In his book “Deep Work”, Cal Newport explains how he manages to thrive as a busy author and academic. “Three to four hours a day, five days a week, of uninterrupted and carefully directed concentration, it turns out, can produce a lot of valuable output.” Just 15 to 20 hours of focused work per week will do the trick. And you’ll still have plenty of time left that you can spend schmoozing and snoozing.

Please don’t blindly believe those hustle culture tech bros who tout how they built their success on relentless work. Even if there’s a kernel of truth to their claims, what they don’t tell you is that they also had the means to mitigate the negative consequences of their self-abuse. Instead, I recommend that you read the book “Time Off: A Practical Guide to Building Your Rest Ethic and Finding Success Without the Stress“. It’s full of good advice like this one:

But as entrepreneurs, managers, and individuals, it’s a dangerous and vicious cycle if we keep assuming that we are productive and effective only because we put in a crazy amount of hard work and long hours, grinding it out. All too often, we get stuck in mediocrity because we are afraid, or maybe just too lazy and comfortable, to question the status quo and the rules set by societal norms.

John Fitch, Max Frenzel, and Mariya Suzuki, “Time Off”