There are places where a voice wants to "shift" into the next register, but much of where it does end up transitioning is choice, more to do with how we have trained the voice. From the studies done by Dr. Gillyanne (The Vocal Process) shown belowon contemporary vs classical singers, where voices "naturally" wanted to shift is different, especially in the women. Classical singing for women is primarily done in falsetto (head voice) so those voices were trained to sing those pitches in a lighter register. Contemporary singers tends to be more "belty" and so the transitions happen later, much where they do in untrained children. Where your voice "breaks" is not set in stone. You have some leeway which can be trained.
Rock singers use an additional vocal muscle in falsetto (head voice) to bring the fold together which makes it sound more like Modal (chest voice) but much easier to transition quite high without cracking or sounding thin. It is sometime called Reinforced Falsetto, although I have heard this term used for Falsetto and Twang, so I prefer to just the term (coined by Aliki Katriou) Rock Set up: Rob Halford (LCA reinforced) sounds nothing like The Bee Gees (twang enhanced.) Both are a type of Reinforced Falsetto.
Thyroarytenoid Dominant AKA:
Chest - Mix - Modal - M1 - TA -"Speaking"
Voice The red is the TA Muscle. The tan is the epithelium. See how the TA is pushing the folds together from the inside and how much surface is touching from bottom to top.
Cricothyroid Dominant AKA:
Falsetto - Female head - M2 - CT - "Talk to your dog" voice
The red is the TA Muscle. The tan is the epithelium. See how the TA is not engaged at all and how little surface is touching, mostly just toward the top.