user15695: I have recently seen a few cases where questions have been closed very quickly (after a few hours), usually with a "question unclear" motivation, but with no further comments to the OP. Examples are:
1) How are colors outside the standard RGB color scheme perceived?  (also highlighted in this meta post)
2) Calvin cycle:synthesis of glucose
3) How many times can a single human stem cell divide?
My feeling is that in all these cases, the questions were dismissed too quickly, without giving the OP a chance to edit and clarify his question. In case (1) the question was initially closed for being off-topic, but was then reopened. In case (2) the question was closed for being unclear, but in my opinion it was clear enough after some edits, and my answer was apparently what the OP was looking for; I have voted to reopen it. In case (3) there has been no further discussion --- possibly the OP gave up after the question was closed.
I agree these questions have been borderline off-topic and/or unclear, especially in the first posted version. But I think it is important that we in such cases point out what the problem is, and allow the OP to attempt to revise the question, rather than just closing it with no feedback to the OP whatsoever.
One danger with closing too quickly is that it is likely to be discouraging towards newcomers; it feel it makes Biology SE appear less welcoming. Also, we should recognize that it may actually be difficult for the OP to formulate the question clearly if he/she is uncertain or confused about the topic. Providing comments and allowing the OP to revise the question are then necessary steps towards an answer. (Personally, I have learnt over the years that in science, formulating good questions is often harder than answering them, and so I have a lot of respect for this process.) 
For these reasons, I think it is important that we err on the side of caution when considering closing questions. My view is that a poorly formulated or borderline-relevant question that remains open for a while doesn't really hurt anyone, but premature closing of a question can be rather damaging because of its discouraging effect.
I recognize that review of questions is a somewhat thankless task where we have too few hands, as pointed out in another recent meta post, and that mistakes will be made. But I would suggest that we try to give borderline cases the benefit of doubt, especially when the OP is a new user, so as to be inclusive as a community. I'd love to hear any comments you might have.

user9943: Short answer 

Vote Early, Vote Often 

Background
The fast closure is a hotly debated topic over the years. There are a few, yet strong arguments that speak in favor of it -

Questions are not closed immediately, they are put on hold first so the process is not final. When questions are put on hold and are subsequently closed, there is time for OP (and other users) to improve the question and vote for re-opening;
Not putting mediocre questions on hold swiftly results in poor questions to linger and start gathering dust, cluttering a site. In CogSci this is a serious  problem and is referred to as the dreaded Garbage Valley. Yes we are out of Beta, and yes, garbage doesn't harm our statistics anymore in the sense we are a full site - but not for nothing! Core individuals here have invested heaps of time in scraping away old, forgotten, poorly posed questions to clean this site up. Not long after this fortunate initiative we were out of Beta. Keep up the good work - kill poor questions swiftly.
It is in fact a core principle of the SE Network: Vote Early, Vote Often. Here in Bio we do vote quickly, but the Vote Often guideline is yet another story...

A small handful of relatively recent related questions 

Shouldn't we be more tolerant with newcomers and non-biologists?
Proposed delay in close-voting
Are we too harsh on new users?


15695: <p>I have recently seen a few cases where questions have been closed very quickly (after a few hours), usually with a "question unclear" motivation, but with no further comments to the OP. Examples are:</p>

<p>1) <a href="https://biology.stackexchange.com/questions/56385/how-are-colors-outside-the-standard-rgb-color-scheme-perceived">How are colors outside the standard RGB color scheme perceived?</a>  (also highlighted in <a href="https://biology.meta.stackexchange.com/questions/3549/visual-dynamic-range-question-mod-closed-why">this meta post</a>)</p>

<p>2) <a href="https://biology.stackexchange.com/questions/56688/calvin-cyclesynthesis-of-glucose">Calvin cycle:synthesis of glucose</a></p>

<p>3) <a href="https://biology.stackexchange.com/questions/56387/rate-of-cell-division">How many times can a single human stem cell divide?</a></p>

<p>My feeling is that in all these cases, the questions were dismissed too quickly, without giving the OP a chance to edit and clarify his question. In case (1) the question was initially closed for being off-topic, but was then reopened. In case (2) the question was closed for being unclear, but in my opinion it was clear enough after some edits, and my answer was apparently what the OP was looking for; I have voted to reopen it. In case (3) there has been no further discussion --- possibly the OP gave up after the question was closed.</p>

<p>I agree these questions have been borderline off-topic and/or unclear, especially in the first posted version. But I think it is important that we in such cases point out what the problem is, and allow the OP to attempt to revise the question, rather than just closing it with no feedback to the OP whatsoever.</p>

<p>One danger with closing too quickly is that it is likely to be discouraging towards newcomers; it feel it makes Biology SE appear less welcoming. Also, we should recognize that it may actually be difficult for the OP to formulate the question clearly if he/she is uncertain or confused about the topic. Providing comments and allowing the OP to revise the question are then necessary steps towards an answer. (Personally, I have learnt over the years that in science, formulating good questions is often harder than answering them, and so I have a lot of respect for this process.) </p>

<p>For these reasons, I think it is important that we err on the side of caution when considering closing questions. My view is that a poorly formulated or borderline-relevant question that remains open for a while doesn't really hurt anyone, but premature closing of a question can be rather damaging because of its discouraging effect.</p>

<p>I recognize that review of questions is a somewhat thankless task where we have too few hands, as pointed out in <a href="https://biology.meta.stackexchange.com/questions/3553/inadequate-moderation-by-the-community">another recent meta post</a>, and that mistakes will be made. But I would suggest that we try to give borderline cases the benefit of doubt, especially when the OP is a new user, so as to be inclusive as a community. I'd love to hear any comments you might have.</p>
 9943: <p><strong>Short answer</strong>  </p>

<blockquote>
  <p><strong><a href="https://stackoverflow.blog/2010/10/19/vote-early-vote-often/">Vote Early, Vote Often</a></strong>  </p>
</blockquote>

<p><strong>Background</strong><br>
The fast closure is a hotly debated topic over the years. There are a few, yet strong arguments that speak in favor of it -</p>

<ul>
<li>Questions are not closed immediately, they are put on hold first so the process is not final. When questions are put on hold and are subsequently closed, there is time for OP (and other users) to improve the question and vote for re-opening;</li>
<li>Not putting mediocre questions on hold swiftly results in poor questions to linger and start gathering dust, cluttering a site. In CogSci this is a serious  problem and is referred to as the dreaded <strong><a href="https://cogsci.meta.stackexchange.com/questions/2091/is-there-a-community-interest-in-bringing-the-answered-questions-to-a-healthy-9/2096#2096">Garbage Valley</a></strong>. Yes we are out of Beta, and yes, garbage doesn't harm our statistics anymore in the sense we are a full site - but not for nothing! Core individuals here have invested heaps of time in scraping away old, forgotten, poorly posed questions to clean this site up. Not long after this fortunate initiative we were out of Beta. Keep up the good work - kill poor questions swiftly.</li>
<li>It is in fact a core principle of the SE Network: <strong><a href="https://stackoverflow.blog/2010/10/19/vote-early-vote-often/">Vote Early, Vote Often</a></strong>. Here in Bio we do vote quickly, but the Vote Often guideline is yet <a href="https://biology.meta.stackexchange.com/questions/3034/why-dont-many-of-us-users-vote-more-often">another story</a>...</li>
</ul>

<p><strong>A small handful of relatively recent related questions</strong>  </p>

<ul>
<li><p><a href="https://biology.meta.stackexchange.com/questions/2877/shouldnt-we-be-more-tolerant-with-newcomers-and-non-biologists">Shouldn&#39;t we be more tolerant with newcomers and non-biologists?</a></p></li>
<li><p><a href="https://biology.meta.stackexchange.com/questions/2987/proposed-delay-in-close-voting/2990#2990">Proposed delay in close-voting</a></p></li>
<li><p><a href="https://biology.meta.stackexchange.com/questions/3107/are-we-too-harsh-on-new-users/3109#3109">Are we too harsh on new users?</a></p></li>
</ul>
