Personally, I like some slow starts. It depends the type of story it is. Especially when it comes to movies and comics, because it's all very visual and I like to be eased in. However, when it comes to a novel, if it drags on for the first entire chapter, you lost me and I won't continue.
For a novel, I tend to stick of Mysteries, horror and true crime books for the simple reason that they have a hook on the first chapter. Usually not very long either, but just something to catch your attention. I'm a visual person and reading long paragraphs bores me to no end.
For a comic, I drop a story because:
- there's no distinction between character.
- have to wait a long time to get a new page up and I don't know what the plot is yet.
- the artwork is too inconsistent or the quality drops over time.
- the characters are too cliché and have no character development.
- A chapter ends with no hook to continue, so I just assume nothing will ever happen.
- The first page is a long novel like backstory. (I get bored and lose interest)
- The backstory is over complicated and long, but told all at once and not brought up until much later and you're even more confused.
- The plot is too simple and obvious. Meaning it's good vs evil and good always wins, but there's nothing in-between and you basically guessed the entire story just by the first chapter.
I personally like slow starts for a series that the plot is more complicated and/or might introduce a lot of characters. Gives a chance for the reader to keep up, you don't want to confuse or overwhelm the reader. If there is a backstory, keep it short and simple and build the story with time or if it's really complicated and it has a lot material, just incorporate it in the comic over-time so the reader can learn it slowly within the story.
My series Megami Shiizun is definitely a complicated one with a lot of layers and quite a few characters. It's gone through a lot of editing and re-work for years. It needs a slow start or else it's too confusing. I want the reader to be asking the same questions as the characters on their journey. You can't rush it.
However, when I introduced the series to Tapas, I uploaded 17 pages in one day. It gave the readers enough material to be hooked.
And, the first page is the first hook, I did a sort of synopsis to make the reader turn to the 2nd page and so on. I didn't want anybody to doze off by over explaining things that I would eventually be repeated as the story moves forward.