https://phabricator.wikimedia.org/maniphest/query/advanced/ has four fields and a checkbox to select projects (!!), and their function is extremely hard to understand.
* "In All Projects" and "In Any Project" sound like yes/no questions to me, so they'd have the same meaning and would be checkboxes.
Tentative understanding of the supposed meaning of the field labels:
* "In All Projects" → "In all the following projects:"
* "In Any Project" → "In one of the following projects:"
* "Not In Projects" → "In none of the following projects:"
* "In Users' Projects" → ??? (T1377)
(Proposed merging upstream: https://secure.phabricator.com/T7197 )
Additionally, the labels are not consistent with the others, which use
* preposition: "Assigned To"; or
* apposition: "Authors", "Subscribers".
Labels should stick to a consistent grammatical construction. Using a verbal predicate where the subject is the task, for instance, would be:
* Is assigned to
* Has authors
* Has subscribers
* Is in projects
* Is in a project
* Is not in projects
* ??? (T1377)
Usage of colons and/or consistent determiners and/or a sensible layout may help making the form simpler to understand.
In general however the form is made a mess by the inconsistent decision of having 4 fields + 1 checkbox (AND, OR, AND NOT, ???, AND NOT *) for one property, and nothing for all the other properties. All the properties should get a consistent interface.