It is well known that fast feedback loops are incredibly valuable in developing software. Methodologies such as teat-driven development (TDD), continuous integration (CI) and continuous deployment (CD) are all designed to speed up the feedback loop. Similarly, in learning & creative endeavours, there is a concept called the short knowledge cycle, which brings the same benefits to knowledge digestion and creation.
When reading a book, instead of finishing a long chapter in one go and coming back to review, or trying to cram many disparate concepts, it is easier to read a single idea (perhaps one paragraph, a few paragraphs or a couple of pages), pause, do a bit of research if needed, link the idea to something you already know, find a few examples to support it, and perhaps take a short break, and come back and repeat the process.
This practice allows you to get multiple slices of work done in a single day, and move large projects forward without being paralysed by not knowing how to start a large complex project or being overwhelmed by the volume of the work.