Some people like to know how things work, they like to take things apart and rebuild them. Linux From Scratch (the distro) might be the extreme of this but Arch seems to strike a decent balance.
Also, you do get more vanilla software from these distro. It's a lot less likely that someone modified the software to work with their distro idiosyncrasies. Sometimes that's a big plus.
I used Gentoo around 2002-2005 or so and I learn a great deal of what I know about Linux through the experience. I now run Ubuntu or Debian cause there are other things I want to learn about ;p
Also, you do get more vanilla software from these distro. It's a lot less likely that someone modified the software to work with their distro idiosyncrasies. Sometimes that's a big plus.
I used Gentoo around 2002-2005 or so and I learn a great deal of what I know about Linux through the experience. I now run Ubuntu or Debian cause there are other things I want to learn about ;p