As discussed yesterday, a Content Management System (CMS) is a way for normal users to add and update the content on a website. But just because they’re easy to use, does that mean they should be in use on every website? No.
It’s a somewhat extreme example, but I’d say it gets the point across. Gmail certainly wouldn’t be what it is today if it were built on top of WordPress. Virtually every well-known unique web service out there is built on a custom foundation; everyday CMSs just don’t perform well enough under those circumstances. Sure, there are things a developer can do to speed them up, distribute the load across multiple servers, and the like, but the fact remains: when everybody uses the same tools using the same components, nobody makes anything better than everybody else.
Most CMSs allow you to do some level of customization. (For instance, some let you develop multiple templates from which to choose on a per-page basis.) But what happens when you want something more unique on a specific page, like a real-time stock ticker, a weather display, or a calendar? There are ways to do these things, but they aren’t always very easy; you’ll probably still need to be able to go in and change the code yourself. If your site is full of these sorts of things, a CMS probably can’t solve all of your problems; chances are, you’ll still need someone who has more technical knowledge.
Just a few static pages
If you won’t need to change the content on your website very often, it would probably be overkill to integrate a CMS into your workflow. For most small businesses, you’d probably end up having a better website if you just emailed a developer every time you wanted to make a change, rather than having to fit all of your content inside a CMS template (and learning how to use a CMS).
In general, I’m a big fan of content management systems, but only when they’re used in the right ways. Hopefully, you now have a better understanding of what their limitations are, so you can make a more-informed decision about whether or not they’d be a good fit for your website.