As Steffoz said below:

"Most WordPress websites are just "brochure websites": they don't expose anything dynamic to their visitors excluding comments, contact forms and search functionality. We already handle these scenarios out-of-the box. Also, every plugin you use that does not have any front-facing components, it's perfectly fine. It's not a hosting solution for every possible WordPress website out there, but it can handle a huge slice of the market, with big benefits for agencies/freelances."

Maintenance problems are those you have when you need to update your installation but you can not because the update break stuff around. I had lots of these :-)