It is always a fine balance to strike between being welcoming and willing to help new users, and letting them get into bad habits which you know they will never shake off.

Questions such as the first one you mention, which tick multiple boxes on the list of close reasons are unlikely to be of use to anyone without significant revision, so they have to be closed as soon as possible. If they then get edited to make them into suitable questions, they can be re-opened, and we try to make it clear that this is what is needed.

Using Stack Exchange effectively is a skill which has to be learned. Anyone who is not willing to learn how to write an effective question, or useful answer, is not going to get very far with Stack Exchange.

Does it really hurt the site if you leave the vague questions open for a couple weeks; give them a chance to be clarified? Give the new community members a chance to participate and learn?

Yes, it can cause significant damage to the site. This is related to Broken windows theory, the more poor quality questions remain open on the site, the more poor quality questions are written. The lower quality the site appears to be, the less likely people are to trust the content of the site and the less likely they will come back here to have their own questions answered.

Compared to many sites, we have quite a relaxed attitude here on Robotics, perhaps too relaxed. I don't go hunting for questions to close, I tend to wait for people to flag or vote to close questions, so they appear in my moderator or review queue. Most of the time, a question which has been brought to my attention does require closing, and although it is rare, sometimes subsequent revisions will get a question re-opened.

My main point is that I think that putting questions on hold as quickly as you do hurts the growth of the site.

Looking at the analytics, the number of questions closed is insignificant compared to the number of new users, but the growth in page views is less than the growth in users, which suggests many people are signing up and then not really using the site.

So what you are suggesting may well encourage the small number of people who get their questions closed, while making it less likely that a far more significant number of people will be turned away due to low quality questions they find when they get here.

It is always a fine balance to strike between being welcoming and willing to help new users, and letting them get into bad habits which you know they will never shake off.

Questions such as the first one you mention, which tick multiple boxes on the list of close reasons are unlikely to be of use to anyone without significant revision, so they have to be closed as soon as possible. If they then get edited to make them into suitable questions, they can be re-opened, and we try to make it clear that this is what is needed.

Using Stack Exchange effectively is a skill which has to be learned. Anyone who is not willing to learn how to write an effective question, or useful answer, is not going to get very far with Stack Exchange.

Does it really hurt the site if you leave the vague questions open for a couple weeks; give them a chance to be clarified? Give the new community members a chance to participate and learn?

Yes, it can cause significant damage to the site. This is related to Broken windows theory, the more poor quality questions remain open on the site, the more poor quality questions are written. The lower quality the site appears to be, the less likely people are to trust the content of the site and the less likely they will come back here to have their own questions answered.

Compared to many sites, we have quite a relaxed attitude here on Robotics, perhaps too relaxed. I don't go hunting for questions to close, I tend to wait for people to flag or vote to close questions, so they appear in my moderator or review queue. Most of the time, a question which has been brought to my attention does require closing, and although it is rare, sometimes subsequent revisions will get a question re-opened.

My main point is that I think that putting questions on hold as quickly as you do hurts the growth of the site.

Looking at the analytics^†, the number of questions closed is insignificant compared to the number of new users, but the growth in page views is less than the growth in users, which suggests many people are signing up and then not really using the site.

So what you are suggesting may well encourage the small number of people who get their questions closed, while making it less likely that a far more significant number of people will be turned away due to low quality questions they find when they get here.

^{† Analytics are a moderator tool, so the specifics can't be shared, but I try to share what information I can within the bounds of what is allowed.}