Something that promotes or enhances well-being; an advantage.
In the context of an OVN (or an open venture) a benefit is an advantage that can be extracted from contributing or participating. Benefits can be tangible (money, use access to physical spaces, tools and equipment, etc.) or intangible (reputation, sense of belonging, sense of purpose, etc.).
It is to be noted that OVNs are built to diminish the possibility of free riding, which is a form of attack on the network (a market failure in traditional economics terms). Thus, access to tangible benefits is conditioned by contributions in some way, through a benefit redistribution algorithm.
Access to governance is a form of benefit and in some cases (depending on the type of governance action) it can be linked to skin in the game. A benefit redistribution algorithm is also used to distribute access to governance.