>>82849266Every stage of childhood involves testing your boundaries, seeing what you can get away with and what is something to avoid.
Infants sometimes cry just to see if they can get the same conditioned response out of a parent that their tiny brain remembers happening before when they actually needed it. A small amount of puking comes from them getting used to the muscles in their stomach and throat they have control over.
Younger kids start to develop desires rather than needs. Part of the learning process at this stage is them slowly learning the difference between a desire (cake, because cake) and a need (fiber in some bread, protein in a meat product, and milk).
Right around the time that self-actualization becomes a thing, they start testing willpower against the outside world. This can occur somewhere between adolescence and early teens. Rather than demanding cake, the demand becomes changing a schedule or winning fights and arguments.
Then you hit approximately 32 where your brain is pretty much locked into the state that it will be for the rest of your life (unless you unfortunately develop senility anyway).
So if you want to change your lifestyle, that's your average number of point of no return. Learn to live with less stress, learn to stop and enjoy the small things, learn to show more empathy, and so on.