# Intuitive UX - locality, controls, squint test

Digested from Erik D. Kennedy, [4 Rules for Intuitive UX](https://www.learnui.design/blog/4-rules-intuitive-ux.html) and [The 3 Laws of Locality](https://www.learnui.design/blog/the-3-laws-of-locality.html). Paraphrased in our vocabulary.

## 1. The three laws of locality (where controls live)

1. **A control sits where it effects change.** The user's eye goes to the place that will change; the control must already be there. "Add" lives at the end of the list, folder actions on the folder, sign-out next to the account avatar. Applies to conceptual groupings too, not just data rows.
2. **A control that acts on a whole area sits above that area.** Refresh-inbox above the threads; app-wide search above page-level search. Recursive: areas nest, and the hierarchy of position mirrors the hierarchy of scope.
3. **The farther a control is from its effect, the more it must pop.** If you must displace a control (thumb reach, corner actions), pay the tax in visual weight - floating compose button, strong color. The best fix remains putting it back where it belongs.

## 2. ABD - anything but dropdowns

Dropdowns hide options, cost extra taps, and collapse under long lists. Replace by option count:

- **2 options** → segmented buttons (equal use), checkbox (off-by-default, applies on save), switch (immediate effect).
- **2–5 options** → vertical segmented buttons (long labels), radios (options carry sub-content), cards, or literal visual choices (show the thing).
- **Many options** → typeahead search.
- **Dates** → near-future clustered dates get a calendar; wide-spread dates get a text field; never a dropdown trio.
- **Counts** → stepper (small quantities dominate).
- **Dropdown tolerated only when:** default rarely changed, ≤3 options, desktop-only.

## 3. The squint test

Squint: the most important thing must catch the eye first, the least important last. Identify the most important thing by frequency of use (per 100 visits, what happens ~95 times?), emphasize it, and demote or delete the rest. His case study cut a form's visible elements from 10 to 5.

## 4. Teach by example

Concrete examples beat descriptions: real use cases on the landing, pre-filled sample data on first load, inline help at the point of doubt, galleries of what others made. A sentence of positioning only lands after the examples.

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## Delta vs our system

**CONFIRMS**
- **Squint test = our 5-second pre-verbal test.** Same rule, independently formulated: the page must communicate before it is read. Kennedy gives it an operational trigger (frequency count → most important thing) that sharpens ours.
- **"Emphasize one, demote the rest" = scarce emphasis.**
- **"The page's heart owns ≥50% of the first screen"** is our stronger, quantified version of his squint priority.

**ADDS**
- **The three laws of locality - we have no control-placement rule at all.** Our system governs reading (type, space, color); it says nothing about where a button, filter, or action goes on a board or form. Adopt verbatim as three checks.
- **ABD control-selection table.** We have no rule for choosing input controls. The by-option-count table is directly usable in eR form reviews and our dashboards.
- **Teach by example / sample data on first load.** Nothing in our system covers empty states and first-run learning; our Jamaica "∅ empty registry" gesture is a seed, this generalizes it.

**TENSION**
- None substantive. This is the complementary half our system lacks: ours governs the reading surface, Kennedy's governs the interaction surface.