Reading with a motive and reading (without a specific motive) are qualitatively different and the former is much faster.
Reading with a motive is reading a paper, book, newspaper article or report in order to extract some specified information, but reading the whole thing because there is no structure to the doucment so you can’t skip to the dedicated section as e.g. you can when reading a textbook - “read the chapter on MLE…“. With the latter, you still usually get most of the meaning of the book and the memories of the book are easier to retain because they were anchored in some specified existing piece of knowledge.