I don’t see this as a major problem. Yes, musers should do their part and search for similar questions before asking. But some questions do deserve a second asking, especially when there aren’t enough or satisfactory answers given before.
I used Quora a lot and had seen repetitive questions being asked. However, as the topic interests me, I don’t mind reading new answers to it. You will always find better answers given in a different perspective. I find that beneficial for the platform.
Instead, I would suggest musers not to post too many questions a day, in the hope of earning upvotes. Some questions that I came across are really unworthy for this platform. A simple 1 minute search on google is enough to get the answer, but yet they prefer to ask it here. What a waste of our time and resource.