Certain tasks such as FX or CFX are valid for both assets (e.g you'd put RnD in there) and shots. Also, we have a Generic task type for people to use if they do something that doesn't fit into other categories.

Currently, task types can be only in assets OR shots but not both, which forces creation of extra task types with a different name. That should be changed (might also require a slight redesign of the Task Types settings page).