Module developers are expected to name things and to provide UI texts but there is little guidance on it. In some cases guidance exists (for example for the format and goal of a hook_help text) but module developers are often not aware of it. In other cases, there is a general understanding, but it's not formulated so that others could follow it in future (for example how to phrase the wording of some buttons). And then there are points where it is not clear whether there is a general understanding (for example whether or not to add a menu item for an admin page).
While Drupal has Coding Standards https://www.drupal.org/coding-standards that detail how long a line of code should be or how to name a variable, we have no such standards to describe how long a module description should be (before it breaks of on the Extend page), or how to name a page or a tab.
Similarly structured UI Standards (or at least UI Text Standards) would allow both core and contrib developers to provide more consistent UIs, and therefore a more consistent UX.
Compile UI Standards (or UI Text Standards) in similar structure as the Coding Standards, and make developers aware of them in the similar way.
First we need to get an overview over what type of UI texts (titles, buttons, labels, help texts, etc.) there are, whether there is an agreed format, and whether some guidance already exists.
Then we could turn that into one list, that at least describes the current status and that could be used already now by module developers as a starting point.
We can then improve that list by formulating missing guidance and where necessary decide on areas that currently seem to be done in an ad-hoc manner.
Such a UI Standard can then be used to identify and fix inconsistency in Drupal Core as well.