How many visitors have left your site never to return after clicking on one of your links to an external webpage?

How many times have your visitors got lost on your site when trying to view videos or images and they forgot where they came from?

How many times have you had to give up the URL of one of your 'secret' sites because it shows in the web browser address bar?

How many times have you fumbled around putting together pop up windows or the like to keep your visitors on your site?