@Switch Blayde
When I hear that a story is slow, I think of nothing happening for quite some time. I'm not saying a reader needs to be hooked in the first sentence or first paragraph, but the author does need to get them involved/interested sooner than later.
"Fast Is SLOW
SLOW Is SMOOTH
SMOOTH IS FAST!"
I will concede that some authors on SOL may use the SLOW Tag incorrectly; indicating that there is some necessary build up / "world building" until some significant plot points may get resolved.
I am okay with that. Actually, I seek those kinds of stories out. In a rich, as in vivid, world, such as JRR Tolkien's Middle Earth I enjoy the Hobbits journeys through the Shire, hiding from the Nazgul, encountering Tom Bombadil, the Barrow Mounds, the town of Bree, waiting on Storm Top for Aragorn, and on to the Last Homy House (Elrond), etc., etc., etc.
The interlude with Tom Bombadil allowed a bit of interaction with ("The One") Ring in an almost uniquely safe place. Also, it is Tom Bombadil who rescues the Hobbits from the Wights (perhaps only Gandalf, or maybe Elrond or Galadriel could have done it, and they had not yet met the other two. For good reasons both were staying in Elf Havens). Tom Bombadil suggests that the hobbits arm themselves, but otherwise not loot the treasures of the dead kings of Andor. Thus, Merrydoc Brandybuck acquires the "shortsword" (dagger) that allows him to inflict damage upon the Witch King of Angmar (also the Leader of the Nine Nazgul) outside the Walls of Gondor.
The acquisition of the dagger occurred in the first third of the First Book: The Fellowship of the Ring. It does not "pay off" until the last third of the Third Book: The Return of the King. "SLOW" by nearly anyone's standards.
I am currently reading Blazing Star by GreyOldWolf https://storiesonline.net/s/24317/blazing-star
(The author did not (mis)use the SLOW Tag.)
I have read the prologue, forward, and six chapters, and I am enjoying it tremendously. There hasn't been much conflict, so far, mostly because the MC, and later his comrades, are being careful, making plans, and they have smoothly resolved the problems they have encountered so far. It seems there are serious problems ahead; however, reasonable awareness of likely problems is why the characters have been conducting themselves in a prudently slow manner.
I don't just use Tags, I also read the Author's description of their story too.
While some writers may be (mis)using the SLOW Tag to indicate a story with a long build up. It seems most readers understand what the Tags: SLOW and NO SEX mean in combination. Even if it is Not the exact SOL definition of the Tags. SOL uses definitions similar to many other sites with porn stories. However, it has many more Non-Sex stories.
I would bet a round of beers that more than 50% of readers (and too many writers) Don't read the List of Definitions on SOL. They just use their "common sense" (or at least their own Expectations) about what particular definitions mean.
I base the above opinion on having read various comments on stories, Blog posts, and in the Forums; the misunderstandings and complaints about non-issues, etc.
"I'll be tak'n it Slllowwww an' Eazy, Baby." Marius