[@Guardian Angel Haruki]

Exactly my point. It is a struggle when it is a forced like struggle and it causes insanity and pain. 

The cluster are in pain because they are all clashing with no choice or hope of escape

Malachite has hope of splitting and so they are in a constant straining fight with one having to stay stronger. Lapis chose to lose herself in Malachite so that her emotions wouldn't get in the way to distract her. She chose to do that for Steven but even then we don't know what that truly did...

A good fusion is having everything in harmony (Stevonnie, Garnet) but even a good fusion if everything isn't in completely harmony it shows (Alexandrite, Opal, Sugilite) by the extra limbs and too many eyes. Rebacca stated that the oddities are because of instability. The more oddities the more unstable they are.