... a chair alone, does not cure all of a child's behaviors.
There is also age related developmental phases and behaviors.
Per cognition and brain development, and development of 'emotions' and impulse control, and attention spans, per age.
A child, also does not come with automatic inherent "coping skills."
These are taught. And learned, and the ability for it, is per age.
Just as communication is, taught as well.
Just as, reactions to situations, are taught, as well.
Just as, management of situations, are taught as well.
A time out chair, does not teach all of that.
Even some adults, do not have, coping skills.
Kids, this age, do not even have emotions fully developed yet. And many children do not even know, the vocabulary for their emotions or what emotion they are feeling, nor can they even tell/communicate to their parent, how... they are feeling... nor, why.
These skills and abilities, are taught.
Look up, the developmental ages, of children.
Per age.
And, time out chairs do not work, for all.
If it did, then all parents would have perfectly understood, children.
And some kids, get desensitized to it.
And don't even care if they are there or not.