Perhaps you know that our rank has a value and an uncertainty, like my rank is “11.4k ± 2.4”
This means that as far as OGS knows, my rank could be as good as 9.2k or as bad as 13.6k
As we play more games, the uncertainty gets less - OGS gets more and more sure about our rank the more we play. I haven’t been playing much (moderating and coding) so my uncertainty is quite high.
Simply thinking, “Humble rank” is the lower bound of our rank. So my humble rank is 13.6k
“But so what!?” you say.
Well, humble rank is used for match making, when our uncertainty is high.
Our uncertainty is high when we first join.
When we first join, our rank is approximately 13k +/- 6k. IE OGS has no real idea what our rank is, but it guesses somewhere in the middle.
You can see that when we join our humble rank is about 19k.
This means that new players are matched with about 19k people instead of 13k people.
This actually solves a big problem we used to have, which is that new players would be matched with 13k players, and both of them would hate that. The new player would hate being matched with someone so experienced, and the 13k would hate getting games with new players all the time.
That’s why, when our uncertainty is high, the matching system uses our humble rank.