I recently posted a question on methodologies and data reproducibility. After finding my answers, I wondered if I was in the right to delete my question given its duplicate nature.
Should people who realize that their questions are duplicates delete their questions?
Questions should only be deleted if they have no lasting value. Your question very likely has lasting value, however:
If you found a duplicate question and answer on this site, your question can direct other people having a related problem to the answer. After all you did not find the duplicate target easily yourself, and others may have the same problem. You can mark your own question as a duplicate without wasting anybody’s time via Flag → should be closed → duplicate of. If the target was difficult to find, also consider whether its 9indability can be improved, e.g., by adding tags, keyword, or a better title.
If you found your answer in some other resource, a similar thought applies: You did not find this resource easily in the first place and your question may help others having the same problem. In this case, self-answer your question. Keep in mind to credit the resources that helped you, refrain from extensive copying and pasting (rather summarise with your own words), and focus on your problem.
I'm not sure what Stack Exchange's view on this would be, but I see a ton of duplicate questions and it usually helps me, not hinders me, because I can combine parts of the different suggested solutions if I need to. There are usually many solutions to a problem and a set of solutions for the first posted question may not work me while the solutions for the duplicate do. This is actually the norm for most of what I go on here for. I would have been SOL many times if duplicate questions weren't allowed to stay.
