On questions that have answers, links that say "modified x mins ago" point to
On questions where there are no (undeleted) answers, the link is to
If you're a 10k+ user and the most recent activity is on a deleted answer, the first link will send you to that deleted answer, which is expected (example). The second link just sends you to the question (example). In addition, questions with only deleted answers don't have "active today" in the upper right sidebar, which would serve as a link to the most recent activity.
This behavior is confusing, especially when there are several deleted answers.