I think 90% of the difference is explained by package load. The more moving parts, the less stable the machine. If you run 10 packages from stable repos, Gentoo

I think 90% of the difference is explained by package load. The more moving parts, the less stable the machine. If you run 10 packages from stable repos, Gentoo will be stable. If you run 900 packages from wherever they were available (more realistic IMO) then it's much more likely to break.