I was asked to review Volume I of set of book written by our assigned technical writer that explained a new programming language which was to be the new standard for system software development in the company. I started into this project and immediately started finding errors, ranging from simple grammatical mistakes, to clumsy presentations, to outright technical errors. Soon I realized that a few scribbled notes would not be enough to convince management how bad this was so I decided to slog through the entire book (about 80 pages) and write down every little thing that was wrong. My finished letter was 15 pages, single spaced. My final summary was "get somebody else to write the book; preferably somebody with programming skills."
My manager thanked me for the useful and detailed feedback and asked me to do a review of Volume II. I refused to waste my time, as they had not understood the point of my effort. Complex programming languages (which this certainly was) require a certain mathematical precision in comprehension that the assigned writer was not up to. For example, compare "Each statement is terminated by a semicolon" (what he wrote) with "A series of EXPRESSIONS are SEPARATED by semicolons" (how it actually worked). Notice the confusion about what do you put after the last expression in a sequence. With no semicolon, the value of the sequence is the value of the final expression. If you DO put a semicolon there, the value of the sequence is zero.