Once a WordPress site is built out with themes, plug-ins, and what-not, the overall number of files necessary to transfer to the client increases. Each requests takes some time. Compiling code into fewer, smaller files can help speed the loading time for your visitors. One WordPress plug-in that enables this is Autoptimize.
Before using this plugin, this page requires 41 separate downloads:
After enabling Autoptimize, there are only 27 requests: