This is a fascinating subject, and great pointers from the previous posts. Form finding is almost impossible to teach as a skill, it just needs to be practiced over and over in any medium available.
Shapes not only have to be interesting and eye catching but relevant to the segment and “makeable”.
I find it amazing how some people can see great shapes in their mind but can’t draw if their life depends on it, so they get great at steering other designers in that direction, using crappy detail sketches.