I skim scenes that aren't hooking me (i.e. I repeatedly read a few lines of dialogue then skip a few lines) until I get to a part that's interesting again.
I find myself skipping dialogue when it feels like the writer is more in love with their own words than with telling a compelling story. If I'm here for the plot, I want it to move at a pace that keeps me engaged, not bogged down by unnecessary verbosity. That said, if the scenes are good, sometimes I'll power through just to get to the juicy bits.
When there is way too much dialog that is bland I'll skip a few sections, but if either I find myself having to go back to find 1 piece of information to answer a question, or I find myself skipping more and more sections I'll just quit.
I usually skim text that I find to be just filler or bland, don't want to end up finding out that there was an important piece of info or context I missed that bad ends me.
I almost never skip, however it happened few times in cases when scene was focused too heavily on watersports or I watch the same cgs for the 3rd time already just with different text because of some corruption progress or other bs.
When I don't know what to expect, I usually skip almost everything just to get an idea if it's something that could interest me in principle or not. Since it's a visual novel, the visual part is what interests me most. Usually, you get a good idea what the story is about just from watching the images fly by. The goal is to get to one or more explicit scenes quickly to see if they match something that could instill arousal. Otherwise, I'm gone anyway. If, on the other hand, as I'm skipping I see something that I really like, I may stop to follow the story. But to be honest, out of 100 VNs I went through, only 10 of them piqued my interest to that level. And even with most of them I get back to skipping because the text is just awful and I simply imagine my own
I start by reading everything, if some parts start to drag on I skip/skim through them, if even then the game is still boring, then that's when I drop it.
There are a lot of visual novels made by people that think more paragraphs equals better writing.
That may work for a book, that require lengthy descriptions and monologues, but a visual novel has that pesky element, the "visual" part of it.
A visual novel should be first and foremost a visual medium, like comics and movies. When the writer puts one thousand words spread through four panels you just know the entire game will be a slog, and in those cases I abuse the skip to see if there anything worth or if I will give it a 1/5 rating.
Brevity is the soul of wit - Shakespeare
I skip if i'm replaying a game and i don't care in watching the scene again or i'm looking for the different content if i'm doing another route. Also if the game is getting boring (and i don't get bored easily) then i'll skip a few dialogues and if it's still boring i'll keep repeating until i read something good...or they start fucking