Like everything else, I look at nature for guidance. In this case the Epidemiologic Triad (
https://onlinecourses.science.psu.edu/stat507/node/25).
My understanding (feel free to correct me if I'm wrong) of it in the context of good websites is
Host: You need a great host/site, something stable & something people want to use
Agent: I consider agents as internal factors like technical, sales & marketing, They help you grow & the ensure stability.
Environment: Environment is pretty much your jurisdiction, you need to make sure that your solution is legal & your environment is supporting of you growing. Another fascinating theory to study around that is the Overton window (https://en.wikipedia.org/wiki/Overton_window).
Vector: A vector, an organism which transmits infection by conveying the pathogen from one host to another, with the most powerful agent been word of mouth.
I guess if you have these 4 components structure well, then you have a pretty good chance of having a successful website according to the Epidemiologic Triad.
Now if you're question is more around business models, then heres also another good resource to look into by HBR
(https://hbr.org/2016/10/the-transformative-business-model)