Everytime I have tried posting to r/askreddit my post has been removed due to it being a common question. But I see repeated questions all the time - how do those posts get through?

I follow a subreddit that crossposts different creepy/scary ask reddit posts. The majority of them are common questions that often appear on r/askreddit and often gain a lot of interaction. I don't mind this as those questions always get interesting answers, but whenever I have tried posting a question in the pass, it was instantly removed due to being a common question despite it not seeming as common as some of the other questions that appear.

Just out of curiosity, why is this?