Certified GKH Gardening Expert
After doing some research, I didn't find any reputable source that recommended propagating cyclamen from stem or leaf cuttings. Especially florist cyclamen, it is recommended to enjoy them while they bloom, then discard.
Hardy cyclamen are easy to grow from seed or by dividing the tubers. Is it hardy cyclamen you grow from leaves? Your successes must be due to exceptional skill. I suspect for most people, the leaves rot before they root.