I was looking at some old questions on Stack Overflow, and I found a question looking for "the best way to do something" that wasn't closed or locked. Here's the question. However, there are some highly upvoted questions closed for the reason Not Constructive:
As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or specific expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, see the FAQ for guidance.
Why are some old questions left open (and not locked with the historical message) that should be closed for this reason?
If you need more proof of this problem, just search for
best closed:no locked:no on one of the Stack Exchange sites.