I read somewhere that StackExchange sites aim at creating a knowledge base that will last for years, maybe decades. Asking "intemporal" questions at Stack Overflow is really easy because the answer to a programming question is unlikely to change significantly during the next 5 years. However, other topics do not always fit this model quite right. I believe that Bitcoin is an example of a topic that is constantly changing over time, at least for the time being.
A lot of the questions asked here will have a different answer next year. Here are a few examples from the highest voted questions:
I decided to ask this now because I stumbled upon this closed question:
This question has 10 upvotes, no downvotes and no close votes. I understand that this subject is likely to change, but so are the questions I posted above and a lot of other questions asked here.