Are labor unions honest in how they chose apprentices?

I've taken tests now four times and been past up over several years. I've been told that I scored higher than most persons, and that I did well on the oral review too. Each time, I am ped over. Each time, it is a relative of the head of the union, or a relative or friend of someone on the board that decides. I'm going to try one more time, and I'm trying to keep an open mind. I feel like it's very dishonest if they are choosing based on who is a relative or friend. Isn't this what unions are NOT supposed to be about? I thought unions were about fairness to workers.