You could create 5 or 6 websites.. or just one!
I've technically created a few "sites" prior to Melvin's World! but these were all just offline files I used to experiment with HTML and CSS before I made the big step to going live.
My ethic is that a personal website is dynamic and grows with the webmaster. If I have a new idea that's completely different from the rest of the site; I just toss it in somewhere and create a sort of labyrinth that rewards exploration. If I don't like something, I could rework it, bury the page (no direct link to it), or just delete the page itself. But make a new site completely? Not a fan of the idea. Still, Never say never y'know? I've only been a formal webmaster for 3ish years.
Here's a brain teaser for ya: What if I renamed my site? Or, what if I changed my host from Neocities to something else? Is it still the same site?