"Life's too short to read bad books"

Quite simply, if you don't like a book, then why continue to read it when there are millions and trillions of other books out there just waiting to be read. I generally have a rule of thumb, that if I'm not getting into a book by 100 pages, then I will put it down - I've actually got three quarters into a book before and put it down because I thought it was that bad. 

Some readers are perfectionists; they like to finish every single book they read, even if they don't like it. I respect that opinion, and I understand it to a certain point, but I don't agree - reading is a pleasurable hobby for me that I would rather enjoy than endure. Why force yourself to read something that you're just not feeling when you could be having the time of your life reading something page-turning and amazing. 

Here are a few reasons why I put books down:

☽ I'm glazing over everything and not really taking it in. This could be seen as me being tired, but I can normally tell when I'm about to fall asleep compared to when I just don't care about a book anymore.

☽ Too many information dumps - the author literally tells you EVERYTHING about their books world, religion, politics, etc, in one big swoop, or multiple swoops as you will. I prefer books where information like that is worked into the storyline, or you learn as the main character learns.

☽ Talking of religion and politics, any book that is too heavily focused on any, or both, of those two areas. (This was one of the reasons why I stopped reading Elantris!)

☽ I'm just generally not getting into it. Plain and simple.

I think it goes without saying, that this is a very personal topic, so I'm interested in hearing why other people put down books, or if they even do put down books.