For some startups partnerships are essential to execution, for instance by giving access to an audience, a technology, or a process. In those situations I have a rule that is based on a fair bit of experience: try to avoid partnering with other startups (David) or the biggest players in the respective market (Goliath). Partnering with other startups is problematic because they may change direction and wind up competing with you, or dropping whatever it is that you are relying on, or possibly ...