To be honest, I never found WordPress easy to use. It's all flowers and rainbows as long as I can find good themes and plugins. However, it starts going south as soon as I need to make a very small custom change.
I've always considered myself an above average web developer, my friends would always have Wordpress websites, and ask me if I can just tweak a few things. Without hesitation, I'd proclaim I could easily make those changes! Then I'd load their site, load their plugin/theme code and css files, struggle for hours to get the desired effect, and even if I got it to work, I would break every other part of their site. ---…
Once you spend some time in the codebase and understand a bit of its legacy history it gets easier over time. A lot of plugins and solutions are aimed towards non-technical users and a lot of overlap. Where we might just write up some custom HTML others might install 3 plugins to make it work.