Knowledge MaxxingData minimisation
Data minimisation is collecting and retaining only the personal data actually necessary for a specific purpose, rather than gathering everything that might be useful someday.
Prerequisite: Privacy risk
What matters
Data that was never collected can never be leaked or misused, which is why minimising collection is one of the most effective ways to reduce privacy risk overall.
Example
A weather app that only requests a user's zip code, rather than their precise continuous location, is practicing data minimisation.
Common misconception
Data minimisation is not about collecting as little data as technically possible regardless of function; it's about collecting only what's genuinely needed for the stated purpose.
Recall question
Why does data that's never collected reduce privacy risk more reliably than securing it after collection?