The thing where flags, arguments, settings, options produce a conflict and the wrong behavior. Ex: Dropdown-Menü for <select> <a>, <b>, or <c> combined with a

The thing where flags, arguments, settings, options produce a conflict and the wrong behavior. Ex: Dropdown-Menü for <select> <a>, <b>, or <c> combined with a checkbox for [all] that grays out the Dropdown but doesn’t change the option to [all] if <a-c> is selected before checking the box. See <update manually>, <install automatically>, <download only>, or [no updates]. Same for multiple handles trying to negotiate system settings and app settings for a database with api calls like the photos app, notoriously.