It is quite hard to find the line between performance issue and relationship issue. I ran into this myself when I had a new manager who wanted to institute policies that to the tech leads seemed nonsense, and I chose to not do what they asked. They took it as a performance issue to the +1 but the +1 turned it into a relationship issue and this was the right call. The problem is that by that time we were both so set in our view that the other was obstructing the way forward that we couldn’t find a middle, and eventually it came down to a hard choice which I “won” by pushing them out of the company. In hindsight I could have made more of an effort to build a personal rapport and get on good enough terms to find a middle ground.