Unrated games

Why some games on LittleGolem are unrated? I have couple of games coming from direct invites that started at the same time and have been organized in the same way, however some of them are rated and some are not. Is it a bug, or where does the distinction come from?

Direct invite games are unrated, perhaps to keep anyone from inflating their rating by arranging games.

But I have played direct invites, where some games were rated and some were not

It also could depend on how many moves a player makes.

I know that some games are unrated if there are no (or very little?) moves, however I'm taking about scenrios when games have been played normally:

E.g. these 2 games were direct invites, started on the same date. However only one of them ended in rating change:
https://www.littlegolem.net/jsp/game/game.jsp?gid=2495963
https://www.littlegolem.net/jsp/game/game.jsp?gid=2495962

Are you sure they were by invitation and not from the Waiting Room?

Yes

Force amjeure and I started two games of Fendo on the same day, March 11, game #s 2495186 and 2495187. These were both by invitation. The first one ended April 23 and was NOT rated. the second one ended on May 15 and WAS rated. The only thing I could think of is that sometime between the two end dates, Richard (webmaster) changed the algorithm ...

And then, I had 2 similar games against gamesorry (by invitation), both started March 18, one ended June 3 and was NOT rated, other ended June 4 which WAS rated :) That would imply, that Richard would need to change the algorithm at least twice after May 15 :)