CMS is fine for a small, static site or blog. But for anything more sophisticated, they are terrible to maintain.
One big company recently asked me to estimate what it would cost to move their cite from one CMS system to a different, more modern one. But the site is relatively old, with literally thousands of pages. And because there is no automated tool to migrate from that particular CMS system to another one, it would have to be done manually and it would take a very long time. I told them so. I never heard from them again, which is fine with me.
Another site I work on is in 5 different languages. But because the CMS they use doesn't support a language plugin (as does, say, Ruby on Rails), each language is effectively a DIFFERENT site, and has to be maintained as such.
I simply don't recommend that my customers use a CMS at all anymore, unless as I say they are just doing a blog or a small, simple, static site. My experience with CMS has been overwhelmingly negative. They may be relatively easy to set up, but in the long run they are far more trouble than they are worth.