Topics Locked After a Week?

Every time I create a post, it says at the bottom that it will close 7 days after the last reply. I understand that this may be because of “not enough interest”, but it may be something pretty important that was not resolved.

A week after the last reply, the discussion is locked, but cannot be unlocked. we are unable to get the answers. Why couldn’t we extend the Waiting Period (the time a discussion waits for new replies until it locks itself) ? I’ve seen some other websites that wait 3 months for a new, good answer. Maybe we could extend the Waiting Time on this website to 2 weeks, or a month?

So basically, my question is:

Why do topics lock so quickly? And what if it’s important? We can’t “unlock” it (obviously).

Any thoughts, ideas, or comments on the said topic?