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Indeed, a title should be descriptive. There can't be two questions with the same title, for a reason: it should be possible to distinguish two questions based on their title. <Bunch of incomprehensible symbols> is a bad title because it's indistinguishable from <another bunch of incomprehensible symbols>.
Questions whose title don't include English words are kept out of the hot questions list, but this is only done for foreign language sites, so it doesn't apply to Puzzling. I don't think keeping this particular question out of the hot list based on its title would make much sense, though: at the scale of questions that do filter into the hot list, this title is descriptive — it clearly conveys “decipher a bunch of symbols”.
I'm afraid your proposed title “Clue for Security to the Party part 12” isn't much better. The question is self-contained, after all — the fact that it's related to “Security to the party part 12” doesn't say anything about the nature of the puzzle and isn't necessary to solve it.
Titles like “The Security to the Party [Part 34]” (and I wish I was joking, but I'm not) are a worse problem. We have about 30 questions whose title says nothing about the nature of the question. And it's getting to be a more and more widespread problem: we have ”Murder of the President - Part 5“, “Name that entity (4)”, “What Am I - Riddle Part 7”, ...
One of the reasons to have unique, descriptive titles is that they are very helpful when searching existing questions. Stack Exchange exists so that questions can be searched. We now have hundreds of indistinctive puzzles. Like hundreds of sites over the Internet.
These interchangeable “brainteaser” questions have completely overwhelmed the site, even though they're officially off-topic. They're drowning out the questions about puzzles. This site has all but become Yahoo! Puzzles.
Some aspects of Stack Exchange still work — voting serves as a poll on brainteaser answers. But Stack Exchange isn't about polls. The bad titles are one more nail in this site's coffin.