Arrrggg!
Yes!
Thank you.
This is the kind of answer I needed.
I was stuck in my head with the examples I read and did and it just did not make sense.
But just the idea of a “health system” and using it in different situations and perhaps not even knowing during development where the info will be used later and how many classes need the information that health has changed and … [imagine a wall of text here] 
Yes. NOW I can think about it in a useful way.
I still hope I get more answers!