Why doesn't turbotax notify you if you completed all taxes but missed the filing part causing me to file late?

Did you efile or were you supposed to mail it?  If you efiled you needed to check your emails to see if it was Accepted.

When you efile you get back 2 emails.  The first email only confirms the transmission.  The second email says if the IRS (or state) Accepted or Rejected your efile.

When you log into your account you should also see the status and if it was Accepted or Rejected, Started, Printed, Ready to Mail, etc.  What does it say?

For a tax return that is printed and mailed, TurboTax has no way to know when and if you actually mail your return. TurboTax does not mail it for you. Your program will always say "Ready to Mail" when you choose the print and mail option.