Maybe
it's a peculiarity of the plant. If you want a great plant, get one started
from seed. BTW, bugs or diseases don't bother it.

Thats it..i read somewhere that in order to get them to bloom on new cuttings,
they have to be rooted them from the plant where it had nevefrom a branch which
had no blooms in the past..which is kind of rare when that plant is in bloom.
I was looking for such a 'branch', but they had all previously bloomed.
Finally, discarded the ones that I had.