I was going to say "meticulousness"..... but I think "care" might be the word I am looking for. I am reminded of Jeff Cooper's thoughts on professional vs. amatuer .... Something to the effect that the pro is satisfied with "good enough", as he does it for money. The passionate amatuer will work at until he gets it perfect.
Winchester or Remington or Blount (or whoever it is that owns Speer now) is responsible to their stockholders: their #1 concern is to make ammo that is
a) safe and reliable as to not cost them in lawsuits and damage to the brand name
b) "good enough" to keep folks interested in "good enough" ammo buying it
c) doing a & b as inexpensively as possible.
The fact that powder "A" is more expensive than powder "B" matters more than whether it is better suited to your particular application...... You, on the othe rhand, can do a little experimentation with YOUR rifle and several powders and bullets...... custom ammo can be as good as you want to make it, as opposed to as good as they figure the mass market will bear.
TheGolden Rule of Tool Use: "If you don't know what you are doing, DON'T."