Why can't you see your original US birth certificate? A certified original copy is not original.?

I find this a bit puzzling and perhaps the answer varies from state to state. I can see my original birth certificate in the state in was born by driving to the Bureau of Vital Statistics in the state capital. I now live in a different state and just called the Records Division of the Secretary of State's office in my state of residence. I was just advised I can see original birth and death certificates, with minimal identification like a driver's license, by going to the State Archives.