All projects has numerous facets that make them come to life and almost always need numerous committees to contribute and be on board with the process.
If a proposal is accepted through both tiers it is a moral duty of other members to cooperate and help the project move forward in the ways that were outlined when it was proposed.
It is also the project leaders responsibility to consider the timelines and other projects other committees might have within the scope of creating realistic expectations from others as well as not making decisions for other committees. If a project on the land for example requires a marketing team to help produce content – such timelines and elements should have been discussed before the project launched and in the proposal phase and not afterwards.