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One minute
to add it.
A lifetime
to keep it.

For people who don't write code: why things rot as they pile up
No. 16Thinking ClearlyPart 4 of 12
1

In one sentence

Making it takes a minute.
But as long as it exists,
you have to keep looking after it.

The expensive part was never building it. It's having to look after it every day afterward.

2

Why this mistake
is so easy
right now

Making things used to be slow. The slowness was a gate in itself: you weighed up whether it was worth it first.

BEFORE
Making one thing took three days
Over three days you'd work out: will anyone really use this?
NOW
Say one sentence, done in a minute
So fast you never get around to asking "do we really need this?"

In plain words: being able to make it is not the same as being able to keep it. The gate called "hassle" has been torn down, and stuff starts piling in.

3

What it looks like
when it all
piles up

More and more optionsSo many that nobody knows which to press
Nobody remembers whyWhy it was set up this way, long forgotten
Old bugs, new placesFixed here, identical over there
"Done" but not doneAll checks green, yet the job isn't really finished

Together these four have a name: "rot". Not that it breaks, but that it gets harder and harder to move. To change one spot, you first have to understand thirty.

4

Someone has
already tamed it

One developer of a utility app had an AI write everything: thirteen versions, 110,000 lines. It didn't rot. He did five things, and none of them is magic:

① Set the framework yourselfWhere things go and how they're split up: a human decides, not the AI
② Let the machine check itselfOver three thousand automatic checks, so no human has to act as inspector
③ Every fix leaves three things behindA new check so it can't come back · a look around for the same bug elsewhere · a note on why it was changed
④ New things must pass a gateNo new constant overhead, no new permissions, and no extra option if a sensible default will do
⑤ Finally, re-run it on a clean machine"Works on my computer" doesn't count
5

The same five rules,
for running
a shop

This isn't a computer-only disease. A shop that's been open a long time catches the same four diseases:

Menu keeps growingAdding a dish takes a sentence, prepping it takes forever
Old rules, no one knows whyIt's always been done this way, and nobody can say why
Fixed at one shop, same at the nextThe same problem, replayed at another branch
Told but not doneYou said it, someone said yes, and nothing happened

So the five rules work in a shop too: set the rules yourself · let the process check itself · leave three things behind after every incident · make new things pass a gate · have an outsider verify at the end.

6

If you only
remember one

"Many things are important only to the people who made them.
The people using them don't care at all." The harshest line in the entry rules he set for new features
Don't add what you don't need Each time you add something, ask: is it worth looking after every single day from now on?
If you can't answer, don't add it yet.
Fast was never
the advantage
In an age where anything can be built fast, the winners are the ones who choose what not to build.
The less you carry, the longer you run.
UP NEXT

A Tick Isn't the Same as Done

Nurses said they washed hands twice as often as they did. Why self-reports drift, why inspectors change behavior, and how to check for real.

No. 25 · 3 minKeep going →
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