>If a question just straight up doesn't interest you or you don't want to answer it, then ignoring it rather than voting it down seems like the reasonable response.Just remember that if you don't give users a built-in and formal downvote button, they will rebel against that UI and invent an informal downvote mechanism to express their disapproval. E.g. a bunch of stackoverflow users would type "-1 downvote" in the comments. If you think a downvote button is bad, a UI that encourages a pollution of "-1" meta comments may be even worse.
(Similar examples of users bypassing web UI limitations would be Github users typing "+1" into issues threads because there's no upvote button.)
Let's say you have 3 rough categories when judging a question such as :
(1) agree / approve --> upvote
(2) apathy / don't know answer --> no vote, do nothing
(3) disagree / disapprove of low-effort question --> downvote
If you architect the web UI to collapse categories (2) and (3) into "no vote" to minimize "hurt feelings" and thus give voters no outlet to express a "downvote", don't be surprised if users rebel and invent adhoc ways to do it anyway.
If you read through the meta thread mentioned in the sibling comment by vasili111, you'll see the well-respected high-karma SO users like John Skeet, etc use the downvote button as a feedback mechanism for bad questions.
### EDIT reply to those (galaxyLogic, randcraw, etc) suggesting forcing downvotes into the comments area:
On the surface, it sounds logical and reasonable to force explanation of downvotes but that doesn't work for high-traffic sites like StackOverflow. (In 2011, Jeff Atwood tried to explain this.[1][2][3][4])
The issue is the asymmetry of work between bad questions and good questions. It's easy to ask bad questions. It's harder to ask well-researched and high-effort questions. This asymmetry inevitably results in the SO site being flooded with bad questions.
Therefore, forcing a "downvote explanation" just adds friction to the goal of filtering out the massive volume of bad questions. This was the rationale why downvotes on questions don't cost any karma. I.e. forcing downvote-commentary works better for low-traffic sites and small communities but not for high-traffic sites.
[1] https://stackoverflow.blog/2011/06/13/optimizing-for-pearls-...
[2] https://meta.stackexchange.com/questions/56817/can-we-preven...
[3] https://meta.stackexchange.com/questions/135/encouraging-peo...
[4] https://meta.stackoverflow.com/questions/250177/require-a-co...