The paradox, as is frequently explained, is that many of the most successful sites are those that people spend almost no time on.
Lets say you go to google, find a search result, and click to leave google. If you do all that within a coule seconds, then google was successful even though you spent almost no time on google. This is similar to that.
Remember, too, to paraphrase paul graham for at least the fourth time in this thread, that the yahoo directory started out as jerry yang's personal collection of bookmarks.
jerry yang's multibillion dollar company bought out paul graham's viaweb and made paul graham into a millionaire.
so consider all that, let it all sink in, and then decide whether you want to tell me that my idea is bad.