A colleague of mine is using milestone to manage high-level quarterly goals. Basically we have a project called #our_team and then underneath that project we have goals which were created in a specific order which doesn't match the order in which these goals were completed. Basically, we created a bunch of milestones and are now in the process of planning our next few months of work. It seems that milestones have an ordering, but it doesn't seem that milestones within a project can be reordered. I'm not sure if there were any plans to add this or not, so I wasn't sure if I should simply comment on T10349.
My understanding is that subprojects are basically just regular projects but with a parent relationship. We didn't want these projects to pollute the projects typeahead because no-one should be creating tasks within these subprojects (given that these subprojects dictate what we are working on). By choosing "milestone" instead of "subproject", it becomes clearer in the project typeahead that the subproject is internal to the parent project. That is, if we made #our_january_goal a subproject then it would show up in the projects typeahead as "Our January Goal" whereas as a milestone it is rendered as "Our Team (Our January Goal)".
Agree, but I think that there is possibly also some ambiguity regarding subprojects vs milestones vs projects. Someone has also just asked me what the difference between a project and a subproject is, as they aren't sure whether some projects should be created as subprojects or as regular projects.
I think it's not perfectly clear in the UI, but we do have it documented:
Subprojects are projects that are contained inside the main project. You can use them to break large or complex groups, tags, lists, or undertakings apart into smaller pieces.
Milestones are a special kind of subproject for organizing tasks into blocks of work. You can use them to implement sprints, iterations, milestones, versions, etc.