Some guys prefer to keep their balls. Running HCG from the start is also kind of an insurance policy in case you ever need to come off. It will prevent primary hypogonadism as long as you're on it.
It's actually painful to me if I go a few weeks without HCG. They get so small, sometimes they go up inside me during sex or a bj. Painful as **** when it happens. I'd rather keep mine the same size they were before I got started on test.