Mouse over criteria in an achievement converts the link to quest instead of achievement.

Reproduction example:

1. Open achievement log
2. Search for Periodic Destruction and open that achievement so you can see the criteria
3. Mouse over 'Osgen' entry
4. Hit the hotkey for creating a link
5. You will now get a link to a quest instead of an achievement

Note:
1, I did not have any other addons enabled
2. There are several types of "criteria" for different types of achievements, some just don't create any link at all (such as: https://www.wowhead.com/achievement=10749)
3. Mouse over outside criteria works just fine