This page in a nutshell: In certain circumstances, a deletion or merge discussion can be closed with a result of "speedy keep" before the normal discussion period ends.
Speedy keep is the process of closing deletion and merge discussions with a result of "speedy keep" before the normal discussion period ends, but without unlisting or deleting the actual discussion. This guideline applies only to "speedy keep" closures; the criteria for speedy deletion cover the circumstances under which pages may be deleted immediately.
Absence of a deletion or merge rationale. Normally, the nominator will start the process by providing grounds for deletion or merging, but if (a) the nominator withdraws the nomination, perhaps because of improvements to the article that happen during the AfD, or (b) the nominator failed to give intelligible grounds for deletion, userfying, redirection, or merging (perhaps only proposing an alternative action such as moving)[1]and no new rationale for deletion or merging appears in the discussion.[2] Exceptions:
If the nominator indicates that the nomination is procedural in nature, then the nomination is ineligible for speedy keep. This includes a "relist" result from deletion review, fixing errors in the nomination process, or if a user stated a page should be deleted or merged on a talk page without actually nominating it.
If the nomination would otherwise qualify for close to speedy redirect then suggestions to redirect the page are treated the same as moving or merging.
Where the nominator withdraws their nomination, check whether other editors still recommend a delete, redirect, or merge outcome before speedily closing. If a good-faith editor in good standing recommends delete, redirect, or merge, the discussion should not be speedily closed using this ground.
The nomination was unquestionably made for the purposes of vandalism or disruption and, since questionable motivations on the part of the nominator do not have a direct bearing on the validity of the nomination, no uninvolved editor has recommended deletion, redirection or merging as an outcome of the discussion. For example:
obviously frivolous or vexatious nominations (such as recently featured content or April Fools jokes)
nominations which are made solely to provide a forum for disruption, e.g. when a contestant in an edit war nominates an opponent's userpage solely for harassment
making nominations of the same page with the same arguments immediately after they were strongly rejected in a recently closed deletion discussion
nominations that are clearly an attempt to end an editing dispute through deletion, where dispute resolution is a more appropriate course
The nomination is completely erroneous. No accurate deletion or merge rationale has been provided.
The nominator was blocked or banned at the time of making the nomination, so they were not supposed to edit. In that case, the nominated page is speedily kept while the nomination can be removed from the log, tagged with {{db-banned}} and speedily deleted as a banned contribution. However, if subsequent editors added substantive comments in good faith before the nominator's blocked or banned status was discovered, the nomination may not be speedily closed[3] (though the nominator's opinion will be discounted in the closure decision).
The page is a policy or guideline. The deletion processes are not a forum for repealing certain policies; such should be relegated either to the corresponding talk page or as a request for comment.
The page or image is currently linked from the Main Page. In such cases, please wait until the link is no longer on the Main Page before nominating. If the problem is urgent, consensus should be gained at WP:ERRORS to remove the link before nominating.
If a page is nominated on the wrong forum (for example, a template on AfD or an article on MfD), the misplaced discussion may be procedurally closed and the page renominated on the correct forum, with the original nomination, and any comments made so far, copied over to the new nomination. The closing comment should indicate where the discussion has been moved. This does not strictly count as a speedy keep, since the page still remains nominated.
Please realize that while you may personally dislike having a deletion or merge tag on your favorite article, template, image etc, the harm it does is minimal, and either the article or the tag will be gone in around a week. Also be aware that the speedy keep criteria, particularly the first three, are not to be used to express strong disapproval of the nomination: a rationale that you don't agree with is still an argument for deletion or merging, is not necessarily vexatious, and does not imply the nominator has neglected to read the page.
A "snowball clause" is not a speedy keep close, and the two should not be confused. The "snowball clause" is a valid criterion for an early close, and is not subject to any of the other criteria necessary for a speedy keep, but it is not a speedy keep criterion itself. Specifically, discussions must meet specific criteria to be speedily kept. "Snowball closes" are justified by "Ignore all rules" and "Wikipedia is not a bureaucracy" as opposed to a specific set of guidelines. For that reason, "snow closes" may be controversial and additional care is warranted. Though the two may seem similar, closes under the snowball clause should never be closed as "speedy keep."
Notes
↑Per WP:AITALK, LLM-generated arguments are not counted as a valid rationale.
↑Unless all such comments support keeping the article, in which case the discussion may be closed as a speedy keep.
When closing a debate as speedy-keep
When a discussion is closed as a speedy-keep, close the debate as you would a standard close, but use the result "speedy keep" instead of "keep". The procedure for administrators closing AfD discussions are laid out at WP:AFD/AI and for limited cases of non-administrator closings, at nominator withdrawal or here.