Plant looks vs. flowering (3 pics)

I'm always preaching about how much you can tell about a plant's health and well being from its looks if you observe carefully but sometimes I really can't figure it out.
I have two Prepodesma orpenii plants of an approximately same age (both initially from Kakteen-Haage nursery). One is, even though a healthy plant, not particularly strong looking. It likes to dry off leaves and leaf tips and is sort of smallish. But it had the strength and willingness to develop and open three beautiful flowers in a row this year! (I'm so proud of it)
The other one looks strong and big and healthy with its perfect juicy leaves but it has dropped its two flowers at an early stage this year and didn't even try to repeat. I guess the meaning of this story is "don't judge by the looks" but that's not true because with plants you kinda have to anyway. Let's better call it "let yourself be surprised" :)

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