It could be that he refers to the standard factory loads for chamberings that are recognized as "inherently accurate", such as the .38 Special.
I never ran across any off the shelf U S manufactured .38 Special ammo that wasn't accurate in every revolver I tried it in.
My handloads were a smidgeon more accurate, enough to make handloading worthwhile, but not entirely necessary.
Some may obtain better effective accuracy from a particular type of handgun by tayloring the load for specific barrel length, or downloading (in charge weight or bullet weight) to reduce felt recoil to extend personal shooting efficiency over long strings.
Such as in ultra lightweight pistols in standard chamberings or in pistols chambered for hard kicking magnum cartridges.
A load taylored for a specific type of shooting may require a much lighter bullet at a higher velocity than available in a standard factory load for best accuracy at the intended ranges, and with less drop to avoid excessive holdover.