I'd be surprised if inborn wrist, toe, and finger flexibility can be increased much by any means, so I'm inclined to believe that hypermobility plus probably stiffness precedes the first sweet crack. Beighton is of limited value in measuring hypermobility, IMO.
If you stop for ages you lose that urge. I finally broke my hold from cracking since New Years Day!!!!!!! As i cracked top joints on fingers properly and it sometimes gets the main joints in fingers so there was no point then.