Working together might means eating together and spending a lot of time with each other. These could be considered as temporary communities, and although it works well when everyone is excited of being part of such, it is easy to fall out of grace.
Washing the dishes, cooking, sharing the food, cleaning the toilets, norms of behaviours that should be widely recognised are often the beginning of the end of a group of people, and the projects might be heavily affected by this physical situation.
The co-living patterns are here to help on this fundamental aspect, they are game or processes which aid maximising the benefits of being together, while minimising all the drama that could come with it. These patters are there to avoid having to deal with the eons-old "free-rider" problem