This is not a problem and it might better go under Tips and Hints than under Discussion, but I found it interesting.
Real example: I was working in RM on a person named John Walter Bray born 1890 died 1948 and RM showed four WebHints for him at FamilySearch. All four of the hints were really for him and two of them were already approved at FamilySearch by some other user. I decided to approve the other two. Processing one of the approvals worked correctly without incident at FamilySearch, but I couldn't process the other approval that RM says was needed because FamilySearch said it was already approved. How can this be? FamilySearch says the hint is already approved, RM says the hint is not yet approved, and RM gets its information about hints from FamilySearch.
I now know the answer, but to make a short story long, let's review how WebHints really work at FamilySearch. Before there were WebHints in RM there were Record Hints at FamilySearch. For a person B in Family Tree, FamilySearch has a process that suggests that record C in FamilySearch's record collection might be a match for Person B. You logon to FamilySearch. You look at person B. You see the Record Hint that says that record C might be for person B. You investigate person B and record C and either approve or reject the hint. so far, so good.
Suppose from within RM, person A is on your screen. With WebHints properly enabled, RM will send information about person A to FamilySearch. FamilySearch will look in Family Tree to see if there is a person there who might be a match. In my case, I'm looking at John Walter Bray born 1890 died 1948 in RM and that's my person A. Some process at FamilySearch takes the information from RM and determines that my person A in RM is possibly the same as person B in Family Tree. The same process also observes that person B already has a Record Hint that suggests that Record C possibly is for person B. So we have a possible match between person A in RM, person B in Family Tree at FamilySearch, and record C at Family Search. In my case, my John Walter Bray as person A in RM and the John Walter Bray as person B in Family Tree at FamilySearch and the record C for John Walter Bray in the records collection at FamilySearch were all an excellent match. So I was good to go, except that FamilySearch said the match was already approved and RM said it wasn't.
A confusing part about the whole RM user interface for WebHints is that RM shows that record C at Family Search is a possible match for person A in RM. The RM user interface doesn't muddy up the water with the fact that the key to the whole thing matching is person B in Family Tree. But when you do the approval, what you are really approving is that record C in FamilySearch is for person B in Family Tree, and then RM shows record C in FamilySearch as a match for person A in RM.
In my case, the problem is that there was an additional person D in Family Tree who was muddying up the water. There were duplicate John Walter Brays in Family Tree, one as person B and one as person D. The query from RM to FamilySearch matched my my person A in RM to person B in Family Tree. The Record Hint in FamilySearch that was already approved matched up record C with person D - the second John Walter Bray. So to solve the problem, I had to merge the two John Walter Brays in FamilySearch - person B and person D. Having done that, there were no other Record Hints to approve in FamilySearch and RM saw all four WebHints as approved in the RM user interface.
The really ugly situation would be if record C in FamilySearch really is for person B in Family Tree, but person B in Family Tree really isn't a match for your person A in RM. In this case, the Record Hint needs to be approved for person B in Family Tree and rejected for person A in RM. I don't know of a way to do that. It could be very confusing and frustrating.