I generally like chapters to be no more than 20 pages long. This is enough to allow for a good amount of story development without becoming too bogged down in details. Of course, there are exceptions to every rule, and I have occasionally enjoyed chapters that are slightly longer. However, I find that anything over 30 pages starts to feel excessive. Once a chapter gets too long, it becomes difficult to maintain focus and interest. As a result, I generally prefer shorter chapters that can be read in one sitting.