I'm trying to think of the number of times that I've self-advocated.
I'm thinking that number is about zero.
Which is probably another one of my issues with life.
And the irony here is that you're a professional advocate for other people.
But yeah, I've definitely seen how not being able to self-advocate has hurt someone. I have a brother who can't do it, and his career has effectively gone nowhere. I remember once he was telling me his manager was planning to promote him to a supervisory position. Several months went by, and it was never mentioned again, but rather than buzz in the manager's ear about it from time to time to keep it on the front burner, my bro kept silent. When he finally spoke about it, it was a moping, "Well, I guess it's not going to happen then..." And my first thought when hearing this story was that if I were the supervisor, I'd point to this as the reason why you should never be promoted.
Self-advocacy isn't really a problem for me. If anything, I have to be careful not to go too far over the top... though there are times when you're dealing with a customer service rep and some self-righteous outrage is exactly what's called for. In those situations, my wife is all too happy to sic me on them.