What "a little better" looks like in practice:

• Rename a confusing variable — you're already reading the code to make your change; if a name confused you, fix it.
• Extract a duplicated block — if you find yourself copying logic, extract it into a shared function before moving on.
• Add a missing test — if the code you're changing has no test, write one for the behavior you're modifying.
• Delete dead code — commented-out blocks, unused imports, unreachable branches. Delete them. Version control has your back.
• Fix formatting — inconsistent indentation, missing line breaks, overly long lines. Small fixes, big readability gains.

The compound effect: if every developer makes one small improvement per commit, code quality rises steadily without ever needing a dedicated "cleanup sprint" or "tech debt week." Over hundreds of commits, the codebase transforms.

The opposite — the Broken Window Theory: if code is already messy, people add more mess. A file with one bad name gets a second. A function with one hack gets another. Quality begets quality; mess begets mess. The first broken window is the most dangerous because it signals that nobody cares.

Martin's professional argument: craftsmen don't just write code that works — they write code that is clean. And they leave every file better than they found it. This is not heroism; it is daily discipline, like a surgeon washing their hands.