It matters because high blood sugar isn't great for the body (nor is low blood sugar). A normal, non-diabetic's blood sugar might spike to 120/130 after a balanced meal. But that same person's blood sugar might spike up to 160/170 after something carb-heavy. So sure, the body corrects for it - but it would be healthier if it didn't go into that higher range at all.

It is very efficient until it's not. When it's not, it sucks. You don't have to have full on diabetes to experience the suck.

> Your body is very efficient as self regulating

Yet the mind of most people is terrible at that, we love to overeat our body regulations.