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Due to extended exposure to wide SE network, hot questions tend to attract certain amount of low quality answers 1 2 3. These answers would better be (and eventually are) removed, but on smaller / subjective-ish sites removal takes quite a lot of time due to limitations in moderation power and inadequate flagging system.
This slowdown in removal, coupled with the way how hotness score indiscriminately inflates depending on amount of answers causes hot questions stick in the list longer than it would be in case of timely removal.
Suggest to adjust aging decay of questions "hotness" to account for amount of answers.
Diluting the brand
Current approach suppresses questions having less answers - given limited capacity of the hot list, this is just another way to say that it indiscriminately favors questions having more answers. This sends strong signal to SE users on what kind content is welcome here.
You may write and refer blog posts about real answerable questions until hell freezes over, but everyday reality of seeing other kind filling the sidebar works totally against the idea of welcoming laser sharp questions having "single correct answer", no matter how you try. As observed in another discussion of related matters, this dilutes the brand:
watching the 'hot network questions' leads me to think that several of the recent sites are gigantic broken windows of self-absorbed subjectivity... The questions are whiney, the answers are opinion, and the voting ... oh the voting.
I try to resist the 'reality TV' temptation to click on hot questions on these sites, but every so often I fail...
For the sake of completeness, brand dilution may be less visible from outside of Stack Exchange, as web searches eventually correct artificially promoted 5 stuff and bring truly valuable / entertaining content back to top, fixing the issue for visitors coming here from web searches. It's SE regulars, active askers and answerers, who take the hit of fake popularity conditioning coming from sidebar, it's them who get a long standing impression that asking questions to gain as much answers as possible is the way to go.
"Protection" that makes a room for damage
The very protection ("penalty") that prevents list from being dominated by Stack Overflow, makes room for it to be dominated by questions from sites less capable of moderating highly exposed content.
Think of SO regulars (making probably the largest audience of the hot list), what do they learn from it? No matter how good are SO questions that get into the list, vast majority of what is promoted there is not like that.
- Yeah average SO user can't see SO questions that fail to get to the list but what they see instead are mostly questions from other sites, encouraging multiple answers. This teaches list audience that it's a norm, that system encourages that. They think wow this works so well at other site(s), let me try something similar at SO. Yeah their attempt will most likely fail 6 and their question will likely be voted down and closed, but, alas, this won't help next guy seeing the same skewed selection at the hot list.
No matter how you close, downvote, educate those who tries it at Stack Overflow, this won't stop new users from trying weird "hot-like questions" again and again and again - simply because that's the way promoted to them from the hot list - every day, day by day, week by week, month by month.