BSD is designed. Linux is grown.
This is such a beautiful sentence.
When developing some serial drivers for a vending machines running linux, me and my team went crazy handling all the hacks, specifications and modules the kernel had. It is just a bloated monster, on a driver I found a comment:
"We don't know why it is this way, but please dont touch it"
The server controlling the vending machines instead run on FreeBSD and its much tidier and organized kernel space has been a pleasure to work with.