Translations:Kernel/Gentoo Kernel Configuration Guide/16/en

There is an important difference between built-in and modular: with a few exceptions, the kernel makes no attempt whatsoever to load any external modules when you might need them (it is left up to the user). While certain other parts of the system may have load-on-demand facilities, and there are some automatic module loading utilities available, it is recommended that you build hardware support and kernel features directly into the kernel. The kernel can then ensure the functionality and hardware support is available whenever it needs it.