I can only speak for myself, but I started out on a single stage press and enjoy the hobby of handloading, that I am not in a hurry to finish so many rounds in so and so time. I don't shoot competition so my many trials, for handguns, are different hard cast bullets, soft or swaged lead bullets for target/plinking, powders and accuracy, and even some of the many jkt bullets I've stockpiled over the years. Same with rifle loads.
I just don't have certain loads worked up for certain pistols and am always trying some new powder or load or bullet.
Bill