This Question which related to dialogue got 10 upvotes.
Whereas this question here got three downvotes, was put on hold and subsequently deleted.
What type of dialogue related questions are allowed here?
You are asking two separate but related questions. You could ask why the upvotes/downvotes? You could also ask why questions get accepted to stay while others get put on hold or removed?
As to the first, if you take your mouse and hover over the upvote button, you will read: "This question shows research effort; it is useful and clear ... [emphasis mine] If you hover over the downvote button, you will read: “This question does not show any research effort; it is unclear or not useful. [emphasis mine]
So a question should: (1) Show research effort, (2) Be clearly stated, and (3) be useful.
In the Scarface question, the author saw the movie many times, and still had a question. In the “meaning of teen words” question, a simple Google search yields the answer.
Questions need to asked clearly. Otherwise, one is bound to draw downvotes.
Usefulness is another key element. This is subjective to the voter, but usually a consensus forms and you observe many more of one vote than the other.
As to whether questions stay on the site or get closed, the question needs to be on-topic to stay. Off-topic questions can and should be put on hold. The Movies and TV help center has a lot to say about this. But you can start here if you like.
The Scarface question asked how to interpret a line because explaining it explains how characters think and act in the movie’s plot. The “meaning of teen words” question is asking a question about how to use the English language – a question for another site.