[Christian]

Thats a consequence of OF's design, originating from the GTD concept.

Base idea is that, whenever you have the ability to complete a task, you sit down and check OF for available actions. If an action is "waiting for"/"on hold" then you can not act on it. Other people have to act first. Hence OF hides it so it does not clutter your view on actually available tasks.

Projects on the other hand are meant to organize individual tasks that belong to each other or depend on each other in order to achieve the greater goal, getting the entire project done. Projects are no tasks. They will not clutter your view on individual tasks since they do not show up there, no matter if they are on hold or not. Still they will be visible, even if "on hold", which makes sense to me since you might have want to work on your project's structure even while waiting for the project to become actionable.

OF requires a little personal commitment, so to say. It does a great job of keeping track of your todos, reminds you and so forth. Still, if you use elements like "on hold" you will have to either set view options to show "remaining" tasks from time to time or use the review function to make sure you do not miss stuff.

However, if you put a task on "waiting for" then there should be a third-party action (the one you are waiting for) which will at some point remind you of the task, no?