Users who want to change linked dates on an article sometimes makes it wrong: they change the label, but not the target. The result on the wikitext is [[2015|2016]] instead of [].
On fr.wp, where it has been reported, there is a regular WikiCleaner report with articles where the date linked is not the same as the targeted page. I've randomly picked up 10 articles on that list: for 9 of them the change has been done by a new user or an IP using VE. On the last article picked, I haven't found the diff.
If people don't understand that they have to correct both label and target, there is possibly a design issue.