> why do 1 move correspondence games affect ratings
 
Three reasons:
- to deter people from starting games and then abandoning them, or going on the waiting list when they're not going to be there to play
 
- so that people who keep abandoning games will slip down the ratings and therefore out of the rating filters of people who really do want to play
 
- because abandoning a game counts as a loss, it is true to the purpose of ratings, whereby rating difference is related to probability of winning.
 
> these are probably
> challenges incorrectly accepted or erroneously accepted by Caissa?
 
What's your evidence of this? The ones I keep getting are matched through the waiting lists. My guess is that too many people put themselves down and then don't have their email notifications enabled and forget to check back at the site. The answer could be to:
- have email notifications enabled by default for new members
- have an email notification that a game has started

> My evidence is my game against pdft8 - I have no recollection of ever
> accepting any challenge - only playing in tournaments - pdft8
> obviously plays or makes many challenges and a high proportion if you
> look at the results are 1 move wins.
 
And a quite high proportion of mine are 1-move or even 0-move wins.
 
> Also I disagree with your points, the ratings should provide a guide
> to a players strength as a chess player and therefore 1 move
> correspondence games should not count. Unlike live challenges where
> players do not respond - which I agree are very annoying and should be
> punished - at correspondence there is very little inconvenience if a
> game never gets started properly.
 
True, but it's downright annoying to the person who's waiting, who doesn't know whether half his/her opponents will ever turn up and therefore how many more games he/she has time for. It's also annoying to make the effort to put up a waiting list entry and have it go to waste.