<p>Voting is an important signal, but for many askers only acts as a signal at all when given before they get an answer they like (because they then don't log in until they have another question).</p>

<ul>
<li><p>If a user asks a good question, there's no loss in upvoting it immediately. Why wait? </p></li>
<li><p>If a user asks a badly formed/somewhat mangled question, there's some argument for giving them a few minutes (say the usual time window in which it counts as part of the original submission) before a downvote. If you see a problem but don't downvote, at least comment on the problem.</p></li>
<li><p>if you do give downvotes (early or not) they should almost always be accompanied by a comment explaining the problem (spam and trolling are among obvious exceptions -- you don't usually need to do more than just downvote and flag). Downvotes with constructive suggestions don't bother me but downvotes where I can't figure out what they're for are a frustration. </p></li>
<li><p><em>failing</em> to downvote a sufficiently bad question reasonably early (and where reasonable, voting to close) simply leaves us with more bad questions and makes the site as a whole less friendly and useful for people who could otherwise find their answers via searching. The people who get their answers via searching outnumber actual posters of questions by (typically) dozens- or hundreds-to-one (i.e. it's the searchers, not the askers, who are primarily being served by the site, even though you don't see them). If they're trying to look through a load of terrible questions we're not helping the largest swathe of people we'd otherwise be serving. </p></li>
<li><p>not getting answers is also discouraging to posters, but better questions have better chances to get answers. Careful use of downvotes is one way toward improving the average standard of questions (and hence the user experience of the people trying to provide answers), so even if you care for neither the searchers nor the answerers, you can still help askers on average by using downvotes well (if a new person about to ask a question sees lots of carefully written questions, it's much more of an encouragement to do likewise than if the new questions list is littered with a barely readable mess -- and then they're more likely to get answers; so it's actually also a service to the <em>next</em> $n$ askers if you reduce the frequency of poor questions)</p></li>
</ul>

<p>However, an important thing to keep in mind is that downvotes should be reversed when the question improves (even if it's not the original poster who improves the question); as soon as a question is edited, you are able to change your vote. Changing a downvote to an upvote because of an improved question is helping people write questions more likely to attract good answers... and that helps everyone (askers, answerers and readers). </p>

<p>Personally I try to use comments for minor problems and try to keep downvotes to a small proportion of my total votes (arguably I should downvote more than I do) but used with care, they  can be a big help to making the site work as it was meant to. Here at CrossValidated we use downvotes a good deal less than at StackOverflow (and even than math.SE if I recall correctly). I don't think we are nearly as discouraging (in this particular sense) as the typical SE site.</p>
