Disappointment in Movements

I have seen repeatedly as I've grown older that movements arise around causes and goals whose core I agree with, but then the movement takes the sentiment a step or five further, into territory that, at the very least, I don't know enough about to know whether I agree with or not. It's this accretion of ideas, this complication of simple ideas, that I find frustrating. And, in the end, even though I might desperately want to support that core of agreement, I can't support the movement, either because I know I disagree with the accretions, or because I don't know, but have circumstantial evidence that I probably will.