Why is smart punctuation so...not smart?

If anything, smart punctuation is making me sound like I'm having a very long run on sentence. It is so bad. Siri wasn't this bad before, but now talking to text is absolutely terrible. Why did this start? What was so bad with Siri before? I've always been able to talk to text, now it's very hard, why? I know the answer to my question is I can turn off smart punctuation, but my real question is… Why is it there when all it does is make my sentences incorrect? There is no way you can use smart punctuation to talk to text a business email or anything. If anything they just added more stuff to my phone that is making it slower. Good job Apple.