On Saving the untitled document- the older untitled document exists and saved as a new one

On Saving the untitled document- the older untitled document exists and saved as a new one

1.Edit a new untitled document .
2. Click save as and save as somename.
3. somename document is saved and opened in a new tab.
4. The existence of the older untitled document with content adds a confusion, if something went wrong and if my document was actually saved.

There has to be a reason for this behaviour. generally when u save a new document , the new document is saved as user document, There is no old new document existing for any reason. User believes his edited new document is saved as his document.

Amar.