IT business skill No. 3: Negotiation
Whereas collaboration is how people who are on the same side work together, negotiation is how people who are on different sides figure out a path forward they can all agree to, even if they don't see eye to eye.
People who don't know how to negotiate in constructive ways will frequently find themselves stuck in situations with no path forward. When they do, they've almost always become the problem -- and don't even know it.