Decision Cards

Make interface decisions you can defend in any design review.

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Design Decisions · Q1 2027

Learn to make these calls on your own.

These cards are the first of many. The course teaches the reasoning behind each one, with practice rounds and teardowns of real products.

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Input & affordance

Ask or Default

Could you answer this question for them?

Use Ask when

There’s no clear majority answer, or the choice has real consequences for money, privacy, or commitment.

Signs it fits

  • Role or use case
  • Plan and pricing choices
  • Consent and marketing
  • Inferences would often be wrong

Use Default when

The system already knows the answer, or most people pick the same thing. Show the value and make it easy to change.

Signs it fits

  • Country, currency, time zone
  • Choices made last time
  • A safe, common option exists
  • Values stay visible and editable

The numbers

Default when the system already knows (location, last choice) or when one option covers most people and is safe. Ask when no option covers most people, or when the choice involves money, privacy, or consent. Consent is never pre-checked.

Say this in review

We know the user’s country from their billing address, so currency is already set and still editable. Roles vary too much to guess, so we ask.

When it flips

The exception

A common default can still be unsafe: pre-selecting the most expensive plan, or opting people into marketing. Common isn’t the same as safe.

See it work

Make the call

Card 5 of 15

A checkout’s ‘Subscribe to our newsletter’ checkbox. Checked by default, or ask?

Input & affordance
The rule

Don’t ask what you can infer. Default to what most people would choose, as long as it’s safe.

From the lesson “Smart defaults & reducing input”

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