Frames are really useful in some occasions. If you are creating a local webpage that serves only for reading, no interactivity involved and the website will not be public on the internet, all the reasons on not to use frames are removed. For example a user manual for an application that is developed solely in html, frames are really useful in keeping a table of contents on the left in a simple and easy to code way. Also if you have proper navigation within the website then the back button ambiguity is removed completely