Memory kits that have been tested by a mobo manufacturer have proven to work with specific motherboard models.
These tests do not cover every kit on the market.
Some memory manufacturers have a list of motherboards for each memory kit that is compatible with specific motherboard models.
Think of the "annoying" memory lists as a way of guiding you towards memory kits that should work without problems.

Sometimes a bios update is required for some memory kits to work.
There may be a comment of "enhanced memory compatibility" for a newer bios version.
Sometimes there are compatibility issues with some memory kits with some motherboard models.

Using memory kits with 4GB modules is sometimes easier than using 8GB modules, and overclocking might be easier with 4 x 4GB instead of 2 x 8GB.
Booting with no memory installed might generate beep code or diagnostic LED errors, but the system will not post, it will usually just sit there doing nothing.