All the folks who use WD-40 like using it. It is easy and dosn't leave any sort of gunk to collect dirt.
Problem is...WD-40 is about as effective lubrication wise, as monkey snot.
IT IS NOT A SUITABLE LUBRICANT FOR ANY CHAIN WHATSOEVER!
Many will argue with me on this, as they feel that since they use WD-40 like thousands of other folks it has to be the bomb...but in reality it is nothing more than a light duty water dispersant with a fantastic marketing team behind it.
Oh sure, you may get a good year out of a ring chain when using it...but you probably would have gotten the same amount of time by using nothing at all.
Find a nice penetrating dry-film type lubricant if you want to see the same sort of cleanliness of your chain, coupled with something that will actually lube the friction surfaces and rings properly.
And if you find such a lube, you will have no more need for a water dispersant like WD-40, as most all penetrating dry-film type lubes are even better water dispersants than WD-40 is.