At some point, every developer has to declare their [primary] allegiance to one CMS or another. They are an essential part of the modern web, and help our non-savvy clients maintain the sites we design long after we have moved on to the next project. I've used a couple in my day (good and bad) and I find myself entrenched firmly in the MODX camp. Bring it on, Wordpress nuts.
First off, I'm a realist. I realize that Wordpress is certifiably huge. What's more, I fully understand that there's a reason for this—no software gets a user-base like it has without doing something right. However, with mass appeal, you have to make compromises to keep that massive base happy and committed to your product, and let's face it—compromise never created an innovative product. Wordpress is safe—but that's not necessarily a good thing.
MODX is different. Where Wordpress compromises to keep the masses happy, MODX provides a completely blank slate: total creative freedom. You can make it whatever you want: a blog, a portfolio site, an e-commerce portal—even an app.
Let's talk about some specifics.
While most CMSs can boast a decent user community, MODX has one that is second to none. There is hardly ever a question asked on the forums that goes un-replied to. Often, you even see the members of the MODX core team on there answering questions.
Not only that, but I have yet to witness the condescending behavior towards noobs that you see on pretty much every other forum out there. Everyone is friendly, helpful and often they go above and beyond to answer any question, be it very simple or very complex.
The community is also very diverse; there are a lot of hardcore programmers, but there is also a plethora of front-end devs (like myself). That brings me to my next point.
When I was starting in the web-design world, I did what most folks were doing at the time: I hand-coded static sites. This allowed for full creative freedom, but made sites very bloated, unorganized and hard to maintain. It was actually this problem that made me seek out a CMS in the first place. I found Wordpress first, and actually launched version 1.0 of this site on it in 2006. While it was great to be able to update content easily, I longed for the ability to do whatever I liked—and Wordpress simply did not allow this. It still doesn't.
MODX is a totally different take on the CMS. Wordpress tries to impose structure, whereas MODX assumes that you will provide it. You can code whatever you can imagine, and once your code is perfect, integrate MODX to manage the content. In other words, you get the ease of maintenance that comes with a CMS, combined with the creative freedom that comes with hand-coding a site. It's a beautiful thing.
While it isn't a hard and fast rule (this is open source, after all), by and large the MODX extras are plentiful and well-documented. Personally, this is a great thing for me, as I have a very diverse client base, and they are continually thinking up new things they need for their sites. I have a stable full of typical extras, but each site brings at least one new request—and there's typically a well-documented extra waiting to fill the role—and the RTFM is growing every single day.
Wordpress documentation is a different story. Often, Wordpress plugins are developed and then left to the elements with very little support. Yes, there are a lot of them, but using them is hit or miss if you're not a seasoned Wordpress expert. I've often found a plugin that is [seemingly] perfect for what I need, only to discover I had no idea how to use it due to lacking documentation. This is a huge deal.
Before the WP masses rise up and burn me at the stake, I wanted to remind you that this is all a matter of perspective. MODX has risen to the task for me so often that I feel an obligation to share it with my fellow devs. Wordpress may have done the same for you—and if so, share your experience! There is a lot more nuance to this conversation, and I'm not trying to paint any CMS in a negative light. As my mother (wise woman) taught me, it takes all kinds. Peace.
Did I help you out?