WordPress now runs a quarter of the web

tl;dr: It's 25% of the top 10 million websites according to Alexa over the last 3 months, and only includes top-level domains (So skips counting the millions of WordPress.com subdomains).

If it were all websites, it'd surely include tens of millions of low-traffic WordPress sites - but none of those are used in this calculation.

The reason that sites opt to use WordPress is that the editorial interface is familiar and the plugin ecosystem is very robust. The reason that sites stay on WordPress is that upgrades arrive for free every couple of months and do not break backwards compatibility.

WordPress's performance has improved over the years largely as a result of the rising tide of CPU and RAM upgrades and improvements to PHP and MySQL themselves — and more recently through integrations with Elasticsearch, which WordPress works particularly well with.

It's also possible to use WordPress as a framework and to develop elegant code using its APIs, which is largely what my firm does (I run one of the handful of agencies that partner with Automattic to provide WordPress consulting to big companies). But that's the exception, not the rule, and most of the prospective developers we interview who have WordPress experience can't use it the way we want.

There are many articles on the web, but they are mostly for very entry level users. The fundamental problem my company runs into with WP is that only a theme can be meaningfully checked into version control. Everything else, including installation of plugins is coupled with entries in the database. And of course the database also includes changes necessarily made on the production instance, like comments to blog posts.

Any thoughts or links to posts on this greatly appreciated.