Recently I answered a question on ELU, and later found that my answer was actually incorrect. I wasn't sure whether it was worth it to correct it, or delete since a proper answer was already chosen.
Should one delete his answer if it's found to be incorrect?
If you wrote an answer that you found to be wrong, you could edit it to make it correct; in the case there is another answer, and your answer would become too similar to the existing one, then you can delete it. In this case, deleting it (if editing is not worth doing it) would avoid that future users, seeing it has a score of 3 (as it actually has), would think the answer is correct.
If you provide links to different resources or you quote different resources, then I would think it's worth editing it. If the text would be too similar even in this case, I would delete it.
Don't edit the answer to replace its text with a placeholder, such as "This is not longer applicable." or "Wrong answer." If you keep doing it for your answer, this would be considered vandalism of own posts. At least, it would be flagged as "not an answer," and moderators could do one of the following actions:
Between the two, it's not said the first is the preferred one, especially if moderators notice you have recently edited your post.
The other reason I would not do it is that your post could attire down-votes.
One of the goals of Stack Exchange sites is to make the internet better by providing good answers to real questions. Retaining an incorrect answer is something of a dis-service to future readers; even if it's voted down to the bottom of the page, it's still there contributing misinformation. If the correct answer has not yet been posted then you can correct yours; if it is, why add a duplicate? Just delete in that case.
I have deleted my own answers when they turn out to be wrong, or do not address the question (e.g. I misunderstood what was being asked), or (on rare occasion) when a later, better answer completely deprecates mine.
Sometimes there is valuable information in a comment thread that will be lost if you delete your answer. Something I've seen in that case is to delete the body of the answer (replacing it with something like "no longer applicable") so the comments still have a place to live. I don't know if that's considered good practice, though.
Whether you should delete any particular answer is your own judgment call, but it is certainly permitted.
