Why are some questions like "What are the most common mistakes that beginners of (La)TeX and Friends make?" allowed on SE while they are clearly among the list of questions that should not be asked?
Chatty, open-ended questions diminish the usefulness of our site and push other questions off the front page.
Your questions should be reasonably scoped. If you can imagine an entire book that answers your question, you’re asking too much.
TeX
as well, His intention to generate/collect newbie's or any Users level common mistakes might be a good one (he does not care about rep and fame) hence Upvotes and 50/50 response on close/reopen votes with special considerations i suppose.