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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Navigation

Tabs or Sidebar

How many destinations, and how often do people switch?

Use Tabs when

You have a handful of peer destinations and people jump between them constantly. Tabs keep every option visible without spending a column of the screen.

Signs it fits

  • Three to five peer destinations
  • Hierarchy is mostly flat
  • Frequent switching within one context
  • Horizontal space matters
  • Growth is unlikely

Use Sidebar when

You have many destinations, often in groups, and people work across sections all day. A sidebar has room for labels, grouping, and growth.

Signs it fits

  • More than five destinations, or groups of them
  • Labels need reading, not guessing
  • Frequent work across sections
  • The roadmap adds destinations
  • Desktop-first product

The numbers

Tabs: 3–5 peer destinations, switched many times per session. Sidebar: 6+ destinations, any grouping, or a roadmap that adds sections. If the labels don’t fit in one row at your smallest breakpoint, it’s a sidebar.

Say this in review

People switch between these five areas all day and we don’t expect more, so tabs keep everything one click away without giving up a column of the screen.

When it flips

The exception

A product with 4 sections today and 12 planned. Choose the sidebar now: moving navigation later retrains every user.

See it work

Make the call

Card 1 of 15

An analytics tool has Overview, Reports, Alerts and Settings. People live in Reports and check Alerts a few times a day. Tabs or sidebar?

Navigation
The rule

Persistent navigation is for destinations users switch between. Everything else is a link.

From the lesson “Choosing the structure”

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