NealWalters.com
Some of them internet marketing courses talk about websites as though they are real estate; and compare having many small sites to having many rental properties.
This is a good analogy, but like rental properties, web sites can get “run down”. A few years ago, I created quite a few sites for SEO and marketing purposes, and I left them on “auto-pilot”. 
But just a few weeks ago, I visited some of them, and was shocked to find problems such as:
1) no new blogs added in a year or more
2) one of them was suspended for an unknown reason
3) one of them had been spammed with links to pharmaceutical sites
4) and a common problem was that my WordPress software was several releases behind.
So just as a landlord must visit his rental properties occasionally, a website “landlord” must visit his web site properties occasionally. There are a few monitors out there that I’m checking into to help automate this job.