They are unconstrained in their advocacy. They push for one part of the system or one point to carry the day. The harder they push, the better their advocacy, even though the harder they push the more unbalanced they're asking the system to be. They simply don't make the decisions, and if their advocacy is followed they are not responsible for anything bad that might happen.
Fiduciaries have responsibility. They make decisions, and if their decisions are implemented they are most certainly responsible for anything bad that might happen. That means their decisions are tightly constrained as they have to make sure that all the priorities are minimally funded.
I was a symbolically voting board member once upon a time. I could pout, I could argue for the most extreme measures to be taken. If I argued extremes at times it was because I thought that over-stating the case might push the status quo in the direction that was good for those I was advocating for. I was pure advocate. I was in no way responsible for any decision that resulted from my advocacy. If my advocacy had horrible results, I could deny responsibility because I just sat back and watched the decision get made by those who should have been more careful.
Then the committee did an underhanded and dastardly thing, one that the organization that designated me as a board member and voter (symbolic or otherwise) had pushed for for years. I was given an actual vote. If we voted to cut something and was on the winning side, actual people were helped and hurt by my vote. If we moved resources from one group to another, I may have been helping one group but I was actively hurting another group. If I voted to suspend a program, real, live human beings would have their lives affected. It took about a day for the implications to finally soak through my thick skull, and when advocates for this or that point of view made their cases I knew that they were arguing for what helped themselves, damn everybody else and their lives. The extremism of the views was obvious--they considered only their own and simply didn't think about others at the present or implications for others for the future. It made life much easier for me that I was in no way accountable for my vote to my "constituents"--my appointing organization couldn't unappoint me. Note that the MD governor is both fiduciary and politician. He's responsible not only for the harm he does, but for those who perceive the wrong done to themselves by a decision as more important than the good done to others.
It didn't help that that year a lot of tie votes, 8-8, were looming. It was clear that there'd be a dozen votes or so in the last month that would affect thousands of people in the organization, and the committee was pretty evenly divided. Part of the reason that the chair pushed to give my organization an actual vote was because my vote would be a 17th. No ties possible without an abdication of responsibility.
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