I used to go to a writing critique class where the teacher liked to twist this one saying to: "The plot sickens" because he wrote horror. He had a twisted sense of humor.
But whatever way you want to say it, the plot must do something to keep reader's nose in your book. If you see that something isn't working in your plot, and can't quite figure out why, I think this site might help you out.
I visited a blog by Martha Alderson, called "The Plot Whisperer for writers" plotwhisperer.blogspot.com last night. I found it very helpful. This isn't to say I don't have lots of other plot helping devices, but I have to say this one had some good visual templates. I joined the E-zine, because this author had some really good blogs on her site, and I don't mind admitting, I can always use an expert's advice.
I like her template for the plot planner--showing the "End of the Beginning" (first quarter of the book), then the line angles up to the "Crisis" at midway in the book, then you have a lull, less action, some more character development and information which draws the main character into the "Climax" of the book, then you have the "Resolution" at the end.
It's good to have visuals like this. There are different thoughts on this sort of plotting steps. But everyone agrees the first portion of the book is 1/4 of the book, the middle is 1/2, and the end is 1/4. The Crises and Climax pull the book along to the end.
I'm going to draw this on a sheet of white printing paper we got from a local printing company that comes on rolls. I like using this paper because I can make it as long as I want, when I'm done I can toss it.
To go and check this out the link is: http://www.blockbusterplots.com/resc/PP.himl
Alderson has many other templates there as well. And she has a Test to see if you lean toward character-driven plots,or action-driven plots, and if you are lean in one of those areas she gives clues as to how to work on it. She has books and DVD's for sale to help you if you're new at this plotting stuff, or just can't get the hang of it.
I'm glad I finally went to her site. Go check it out if only for good solid advice on plotting.