Different browsers render frames inconsistently, which can mar your design. Different browsers disagree on the attributes of framesets and frames.
Some browsers render frames inconsistently because of slight errors in the browser program.
Alternative Web access devices cannot render frames at all. Lynx, the text-only browser, does not render frames. Some browsers allow the user to disable frames. Some users have a vehement dislike for frames because of their early bad experiences with frames. Frames make it difficult or impossible to bookmark particular information in your site.