'Perpetuum Mobile' Effect

A guy sets up a website, optimises it and gets loads of traffic from Google. Site ads feed PayPal which pays for hosting subscription and automated domain name renewal. The site virtually runs itself.

What's wrong with this picture? The guy who set it up has been dead for over a year. Chilling.

Question: Is this a true virtual perpetuum mobile or is this website going to stop eventually. Also what is most likely to stop it first?

a) Change in Google algo and drop in traffic.
b) Stale content will reduce the value of the site.
c) Hosting company will go bust.
d) Someone will hijack his domain.
e) Something else.

PS: Please do not ask for the URL.

So What is the url ?

Well if the wfole thing i a forum, or other user generated content stuff, it might grow well forever. On the other side, what you say is that there is no competition out there being better than a dead guy:-)

Not quite a forum, more of a resource based site for beginners in web design and HTML, so I guess the information itself could get outdated and eventually become less relevant and less interesting causing the site to terminate just like its owner.