User:Quiddity/Collapsing and hiding

Content can be "Collapsed / Hidden" in a few ways. There can be situational benefits, but many risks/drawbacks.

Why
The goal is often to deal with a problem of signal-overload, or design constraints.

It can sometimes be good for making things seem less overwhelming or more comprehensible at first glance.

Where
It is used in places like:
 * software toolbar menus
 * complex software menus have to be collapsed. Otherwise they look like this horror[see screenshot]. (But where to draw the line is the complex aspect.)
 * navigation templates
 * (navboxes galore)
 * whole page-sections
 * Minerva skin everywhere
 * m:Answers pages
 * archived discussions
 * in contentious situations (to halt an offtopic or uncivil argument)
 * in rare sheer-deluge situations (to keep everything available on a single really long page, but still feasible to access in the right location/context.)
 * in some software (e.g. the "resolve topic" feature in Flow)
 * galleries
 * at arbitrary cut-off points
 * preferences
 * Some settings are exposed to user-control, but some are "hidden preferences" that can only be adjusted with arcane user-JavaScript/CSS.
 * data-tables
 * E.g. a few people dislike the detailed climate tables in Enwiki articles, so those are often collapsed (Manhattan) but not always (London).

Risks and drawbacks
However, Collapsing/Hiding content has many risks or drawbacks:
 * Accessibility risks
 * Makes it impossible to "ctrl-f" search for that content. cf. T216789
 * Requires interaction. More effort is needed to see that content.
 * i.e. instead of just "(1) scroll", we now have to "(1) scroll, (2) notice the UI feature, (3) reposition mouse-cursor or finger to the [show] link, (4) click the [show] link".
 * As well as being annoying to many average users (e.g. trackpad-users), this is also very bad accessibility for users with fine-motor-control challenges (e.g. Parkinson's disease)
 * Excludes by design.
 * Content-access risks
 * Makes it less likely that anyone will see content in order to read/learn/use it.
 * it's like being on page2 of google results: A terrible SEO outcome.
 * Makes it impossible to 'skim' the page and see that content.
 * it breaks the entire interaction-mechanism of "skim until something interesting catches my eye", whether that's a keyword in a sentence, a blue link, a table, an image, ...
 * w:en:WP:COLLAPSE cautions against using spoiler-warnings or hidden sections.
 * Content-Creation/Maintenance risks
 * Makes it less likely that anyone will update/improve/edit a particular section.
 * This breaks the cornerstone philosophy of "many eyes make all bugs (questions/problems/imperfections) shallow" which is how open-content all works.
 * Out of sight = Out of mind.
 * Confusing UX risks
 * It's easy to miss, or not understand, the "[show]" links or "►" icons.
 * Collapsing all sections on a page makes the Table of Contents semi-redundant, but many people will miss the ToC if it's not available.
 * Social risks
 * Problems for community-awareness.
 * It can make the people who are trying to "keep on top of it all" miss more things, accidentally, if they don't notice something that was "hidden", because someone else had decided it belonged in a collapsed [talk-thread / page-section / template-parameter].
 * FOMO increases, leading to abstract stress.
 * At a broader perspective, it even relates to basic transparency principles. Applying to things like meeting-notes, decision-ownership, ...

TL;DR: I strongly caution against using "hidden/collapsed" as a default, in any of the many senses.