There are soooo many great comments here - both on the PB side & the commercial side.
To us, the cow is number one, since we use AI. She is our mainstay, must be great. We are a seedstock producer but we, like most seedstock & c/c producers, sell to the feedlots also. Remember, 1/2 our calf crop is bulls, and I don't know about other breeders, but not every calf with testicles is bull quality. We castrate most of our bull calves and some go to a feedlot and some we retain & put on a feedout program. So high quality steers & carcass also matters to us - greatly. That represents a good percentage of our income. Also, sell some steers for show.
So, breeding AI gives us the opportunity to pick one bull to match one cow. Now I don't buy semen from 40 different sires, but I will breed to 6 or 8 different sires.
We do try a new young bull most every year, on 2-3 head, but he has to be backed by pedigree, phenotype & numbers (actual & predicted)
Great comments everyone.