(This is a quick post expanding from my old comment, just so to keep it in one place)
It still strikes me interesting how easy it is to use 1 to 5 range as reference for being's stat / skill level in a number of systems, despite the systems themselves then using a widely different mechanics. "1" won't be the same in each of those systems and won't be mathematically equal across them, but it will mean the approximately same level of competence/power in each system.
Systems I can think about where it applies:
– dot system of WoD-like where it represents the number of 1d10 dice rolled against a threshold for successes; average PC has 1-to-5 dots in attribute and / or 1-to-5 dots in skill.
– proficiency modifier in 5Ed, shifted up by one so it becomes +2 to +6.
– "Savage Worlds" dice steps (1d4 as "1", the weakest, 1d12 as "5", the strongest).
– comparable with 'Lamentation of Flame Princess' pip skill system, with X-in-6 chances to roll success on 1d6 die.
– comparable range for GloK sum/dice investment system, shifted down by 1, to become 0 to 4.
– comparable with 'Cats RPG' system, where PCs have 1 to 5 d6s to roll and count even/odd successes.
– stretchily comparable with 'Dark Souls' weapon scaling, with S being 5, and D being 1 (and E being 0 because nobody is thrilled about E-scale weapons)
Technically 1-to-5 is 0-to-6 with exceptional cases going below and above, but 1-to-5 seems to be a good range to reference. I am curious in how many other systems it might be also applicable.