For some it's a matter of winning on the table. Simply producing a rabbit that physically is all that it can be for winning on the show table. I like doing that with my polish. I have to admit it's fun. :)
For others it's producing a rabbit that is temperamentally sound and of a good size for selling to the pet market. Doing that with my holland lops and my guinea pigs gives me a huge feeling of satisfaction. Not that I don't focus on that with my other rabbits as well. :)
For others it's reducing the amount of time needed to get your rabbits to make weight for providing food for the table, or food for their animals, or for the animals of other people. I have to admit, I'm not where I want to be with my meat rabbits, but I'm getting closer. :)
They are all great goals.
It means work and effort.
It means choosing animals for your herd that will further your goals.
It means deliberation and thought, and not just randomly throwing two rabbits together.
This is what makes a breeder.
This is what makes for a good rabbitry.
That thought and deliberation, followed by good animal care.