I don't see any guidelines for down-votes. I thought that they should be reserved for answers that are wrong or misleading, not for correct answers that maybe aren't quite as good as others. Am I wrong?
Nick gave the "closed form" answer. The longer version can be found in the help section: https://electronics.stackexchange.com/help/privileges/vote-down
When should I vote down?
Use your downvotes whenever you encounter an egregiously sloppy, no-effort-expended post, or an answer that is clearly and perhaps dangerously incorrect.
The "closed form" guidelines for downvoting are in tooltips of the downvote buttons
for answers: "This answer is not useful"
for questions: "This question does not show research effort; it is unclear or not useful"
The downvoters are prompted to leave a comment explaining their reasons for downvote.
When a question should be closed (and down-voted)
If it doesn't live up to the quality criteria described here:
This means that questions have to be specific, on-topic, narrow, reasonably researched/trouble-shooted in advance. And it has to be a question, not just a random statement.
Questions asking for recommendations of components, places to buy, tools, libraries and other off-site resources are off-topic.
Questions asking for help with homework must demonstrate research effort and be specific, with schematics, calculations or source code provided if needed.
Questions requiring readers to go through lots of off-site resources may be closed too, on case-to-case basis. Schematics, pictures and source code should be posted on-site, not through a link. Links to external datasheets are however fine and encouraged.
When a question is closed, it is first put "on hold", to give the OP a chance to fix it. After a while, the status automatically turns closed and then it may eventually get deleted.
When a question should be down-voted (but not closed)
If a question shouldn't be closed, but lacks in quality, it should be down-voted. This is a bit subjective but the purpose of down-voting is to encourage the OP to improve the post.
If some things are unclear or contradicting, if the question is sloppily formatted or hard to read for whatever reason. Etc. Things that make it bad, but not bad enough to warrant closing.
When an answer should be down-voted
Same quality criteria as for questions, if things are unclear. Technically incorrect or unhelpful answers should be down-voted.
It is polite but not required to:
- Leave a comment when you down-vote. Constructively explain what you don't understand and what needs to be clarified or fixed. I would recommend to not write "I downvoted because...", since that only tends to create drama.
- Re-visit a post you have down-voted and see if changes have been made to it, then undo the down-vote.
- Delete any previous comment you have made if the problem you pointed out has been fixed, to reduce clutter.