What a Career in Security Taught Me About Paying Attention

In 1986, Clifford Stoll noticed a 75-cent discrepancy in a computer accounting log.

Most people would have rounded it off, assumed a system error, moved on. Stoll didn't. He pulled on that thread for ten months until it led him to a KGB-connected hacker moving through US military systems. The whole story is in The Cuckoo's Egg, and it's less a thriller than a lesson in what sustained, patient attention to small things can actually produce.

I read it years into a career in security. By then I already understood the principle, but seeing it laid out in that detail, one man, one anomaly, one decision to keep looking, made something click differently.

The discipline of security is not really about technical skill, though that matters. It's about the quality of your attention. Whether you notice the thing that doesn't quite fit. Whether you follow it.

What the job actually trains you to do

Security work is slow most of the time. You're reading reports, reviewing code, examining language in documents, looking for the thing that's slightly off. The signal that something is wrong is rarely loud. It's usually a word used in an unusual way, a clause that technically permits something it probably shouldn't, a pattern that doesn't match what came before it.

At Immunefi, where I spent years reviewing vulnerability reports and managing bug bounty programmes, a big part of the work was mediation: understanding exactly what the programme language said, what it could be interpreted to mean, what a whitehat might be able to argue, what a client might contest. The difference between a valid claim and an invalid one often came down to a single sentence. Sometimes a single word.

That trains you, over time, to read everything more carefully. Not with suspicion, just with attention. You start noticing how people phrase things. Which words they choose and which they avoid. Whether the framing of something shifts depending on who's in the room.

I didn't decide to carry that into the rest of my life. It just came with me.

The 75-cent principle in everyday life

Stoll's 75-cent discrepancy is a useful metaphor because it was so easy to dismiss. It was small, it was probably nothing, and it would have cost him nothing to ignore it. The only thing that made him look closer was a disposition toward noticing.

That disposition is something you can either develop or let atrophy. Security work developed it in me. But I see it clearly now in other parts of life.

In a conversation, I notice when someone's words and their tone don't quite match. When something is said carefully in a way that suggests the careless version would reveal more. When a question is answered with a question.

In writing, I notice the sentence that's doing too much work. The paragraph that's there to fill space rather than say something. The conclusion that sounds confident but hasn't quite earned it.

In my own journal, I notice when an entry is circling something rather than landing on it. That circling is usually the thing worth writing toward.

None of this is overthinking. It's more like having the volume turned up slightly on what's already there.

Thinking a few steps ahead

The other thing security trains into you is consequence thinking. Before you do something, you ask what it opens up. What it forecloses. What someone else might do with it that you haven't anticipated.

This isn't paranoia. It's just a habit of holding slightly more of the picture in mind before acting. You get used to asking not just what this does, but what this enables.

I find myself doing this now in conversations, in decisions about how I spend time, in the way I read a situation. Not always consciously, more like a background process that flags things for a second look.

It makes you slower in some ways. More deliberate. You don't always fire off the first response. You sit with something for a moment and ask what you might be missing.

That slowness used to feel like a professional liability in certain rooms. Now it feels like the thing I'm most glad I kept.

What attention actually gives you

There's a version of this that sounds like anxiety. Always watching, always reading between the lines, never fully off. That's not what I'm describing.

The attention I'm talking about is quieter than that. It's more like presence with a sharper edge. You're not scanning for threats. You're just actually here, taking in what's in front of you rather than running a half-speed version of the scene while your mind is somewhere else.

My daughter is three and a half. One of the things I notice most, on the days when I'm genuinely present rather than physically there, is how much is going on that I'd otherwise miss. The specific word she uses for something. The way she tests an idea before committing to it. The thing she's working out in real time.

That kind of noticing is the same muscle. Different context, same disposition.

Stoll followed a 75-cent thread for ten months because he was the kind of person who noticed things and then stayed curious about what he'd noticed. The technical knowledge helped. But the attention came first.

I don't think you need a career in security to develop it. But I do think it needs to be practised deliberately, because the default is to let it slide. To skim, to scroll, to half-listen, to move on before something has fully landed.

The journal helps with this too. Not as a record, but as a place to slow down long enough to actually look at what's in front of you. To notice the 75-cent discrepancy in your own week before you round it off and move on.

This week, pick one conversation and actually listen to how it's worded, not just what it's saying. Notice what's being chosen and what isn't. You don't have to do anything with it. Just pay attention.

See you soon.