After working WP for quite a few years the problem as I see it it that it 'needs' to be all things to all people. Can't code? Not a problem. WordPress.
Before even considering working with a client with a WP site I have to look at what plugins they are using. If they don't have a developer on board (or at least a competent one that built it originally) you know that that it will be stacked with 'useful' plugins. And this is the bit where the issues arise as working out the provenance of each and every one of them and whether they are still supported and/or won't break the functionality of another plugin is pure guesswork. Case in point enabling a nondescript plugin on one client's site broke the main image slider.
Before even considering working with a client with a WP site I have to look at what plugins they are using. If they don't have a developer on board (or at least a competent one that built it originally) you know that that it will be stacked with 'useful' plugins. And this is the bit where the issues arise as working out the provenance of each and every one of them and whether they are still supported and/or won't break the functionality of another plugin is pure guesswork. Case in point enabling a nondescript plugin on one client's site broke the main image slider.