Toptal
WordPress is a very popular way to get a site up and running quickly. However, in their haste, plenty of developers end up making horrible decisions. Some mistakes, like leaving WP_DEBUG set to “true,” may be easy to make. Others, like lumping all your JavaScript into a single file, are as common as lazy engineers. Whichever mistake you manage to make, read on to find out the 12 most common WordPress mistakes that new and seasoned developers make.
Source: Toptal