There are a good number of very valid reasons for drinking beer, but
the one that takes the cake is called the "Buffalo Theory". It
originated in America and goes something like this:

A herd of buffalo can move only as fast as the slowest buffalo, and
when the herd is hunted, it is the slowest and weakest ones at the
back that are killed first. This natural selection is good for the herd
as a whole, because the general speed and health of the whole group
keeps improving by the regular culling of the weakest members.

In much the same way, the human brain can only operate as fast as the
slowest brain cells.

Excessive intake of alcohol, we all know, kills off brain cells, but,
naturally, it attacks the slowest and weakest brain cells first. In
this way, regular consumption of beer eliminates the weaker brain
cells, constantly making the brain a faster and more efficient machine.