This question already has an answer here:

When we ask any question and in some time span we got the answer somehow and now we don't need the answer of that question and I put the answer of that question for others help and click on submit answer it shows time restriction or we can say condition.

So my question is why there it is?

marked as duplicate by Frédéric Hamidi, Martijn Pieters, Shadow The Princess Wizard, Aziz Shaikh, gnat Dec 16 '13 at 9:53

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