Guidelines for checking viability before proposing site

Question

I am asking for discussing the guidelines about checking viability of proposal before making it.

So, The main topics/cases that need guidance are:

1. Proposal is also on-topic for another site. (example: this for proposal created by me)
2. Proposal topics overlap with existing site.
3. Proposal can be considered as duplicate of existing site.
4. Proposal topic doesn't feet for or meet the philosophy of StackExchange

Note:There may also be other topics that should be pointed out ^{comment for adding/improving}

So, What are the guidelines in case of above topics before proposing site?

Broadly, "The guidelines for examining the viability of proposal" is expected from answers.

Answer 1

The top line at What is "Area 51"? is "If you have an idea for an expert Q&A site, propose it here." There are a few other criteria as well. and many of your questions are addressed in the section "Should my idea be part of an existing site, or its own site?"

But in short, you can post any proposal that you feel fits in the guidelines of the FAQ and what you know about the SE Family. Area 51 is all about checking the viability of the proposal. If we could define viability without Area 51, it would be discontinued.

Only a small percentage of proposals make it to Beta launch, some Beta launch and still get closed. Some only last a few hours or days on Area 51, others make it a couple of years before closing. If you have a suggestion, propose it. If it has failed before, that is OK, if it might be a duplicate that is OK, as long as you feel like it could be a success, make the proposal.

Answer 2

Very useful information I found on merging season.

If your idea is largely on-topic on existing site, then It is better to contribute existing site because bigger is better:

The Stack Overflow experience taught us one thing pretty unequivocally: bigger is better. We didn't make Java Overflow and .NET Overflow and Ruby Overflow, we made one big site for all programmers and told them to use tags and, lo and behold, it worked. Why?

1. Critical Mass. A wider site is more likely to attract enough people that questions actually stand a decent chance of getting answered.

2. Rich, interesting information. A broad site is more likely to attract people who want to learn something a little bit outside of the problem that they're having right this minute.

3. Easier to remember and share. Stack Overflow grew to be successful because programmers told each other, "try asking on Stack Overflow." If we had made 2500 different sites for every possible niche programming technology, nobody could have known about all of them.

So. We should just make one or two gigantic sites, right? OK, done.

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[There are also some examples that explains what's the right size domain for a Stack Exchange site? interesting - check it out!]

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We need some rules!

Here's the best we could come up with for deciding whether site X should be subsumed by site Y:

1. Almost all X questions are on-topic for site Y

2. If Y already exists, it already has a tag for X, and nobody is complaining

3. You're not creating such a big group that you don't have enough experts to answer all possible questions

4. There's a high probability that users of site Y would enjoy seeing the occasional question about X

^{Note: This rules are also shown on FAQ.}

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Extra Information:

Right now, there are a ton of active proposals on Site 51 which are, in our opinion, too small to justify their own Stack Exchange sites.

.................

That said, we're firmly committed to the ideal that the community itself has to make the ultimate decisions, so in the coming weeks, we'll be building mechanisms that make it possible to discuss and hash out possible proposal mergers. In any case, there's a huge amount of value to getting these small factions together so they can join forces in setting up large, robust sites that genuinely make the Internet a better place.