We've learned recently about the vast number of Linux distributions that exist, created by hobbyists, professionals, large enterprises, and others. While there are significant differences between some distributions (e.g. Slackware and Fedora), others are more alike (e.g. Ubuntu and Mint).

Select any three distributions within a single Linux family (Debian, Slackware, Red Hat, Enoch, and Arch), or three of the independent distributions (e.g. Linux Router Project / LEAF, Linux From Scratch, OpenWRT, etc.), and discuss their similarities and differences. Why would someone choose one vs. another?