This answer was deleted 2 days ago because 3 users voted to delete the question, but the page wrongly claims that the answer was deleted 2 days ago by the owner. Browsing similar recent examples shows that the problem may be related to the fact that the answer had been temporarily deleted by the author sometime in the past (here 9 months ago).
Second, there was no notification of the deletion. It is not listed in the recently deleted answers page linked at the end of the owner's answers page. Update: Arthur found a Meta.SE answer which claims this list is limited to deleted answers that were posted in the last 60 days. Thus any older answer that is deleted is essentially under the radar. Why not treat older answers the same as newer answers? There is not necessarily any correlation between the quality of an answer and its age.
Is there any convenient way to monitor deletions? The recent deletions list in the 10K tools overflows so quickly that one would need to check it a few times a days to see everything. Once a deletion disappears from this list it seems to be difficult to impossible to locate it again. Without better checks and balances on deletions it becomes possible for a very small group of users (3) to exert unchecked control of site content.