In my hybrids, i consider there's three types of bulb production. Fast, medium and slow bulb production.
And there's also 3 types of clumps based on bulb production. Fast; usually they multiply like scallot. You can found this in candida, rosea, etc. This type of clumps are quite attractive in the landscape, as they provide lots of greens like grasses or daylilies but usually will give you small size bulbs and lots of them which cause most of these types usually are shy blommers.
Medium; usually they multiply like primulina, miradorensis, etc. These types of clumps These types could provide medium to large size bulbs, and the clumps types are like fast type, but with less leaves. These types usually the most prolific and could provide lots of bloom, but its not always like that.
Slow; slow growth and bulb production in zephyranthes came from their species ancestors. You can found these traits in katherinae, drumondii, citrina, etc. They do not provide you clumps, as they are only one but big bulb, so you need to make it artificially. Usually these types are prolific with large size blooms. But they do multiply but in a very very slow mode and sometimes they dont.