Many classics like this are so good because the author is among the first to observe new phenomena. They can write down what they have learned without cultural narratives that distort reality.
The hardest lesson in the book is the chapter 11 "Plan to Throw One Away". I have never seen this not to be the case in large systems. You must design the system to be rewritten. Accepting this is still a taboo.
> In most projects, the first system built is barely usable. It may be too slow, too big, awkward to use, or all three. There is no alternative but to start again, smarting but smarter, and build a redesigned version in which these problems are solved. The discard and redesign may be done in one lump, or it may be done piece-by-piece. But all large-system experience shows that it will be done.2 Where a new system concept or new technology is used, one has to build a system to throw away, for even the best planning is not so omniscient as to get it right the first time.
>The management question, therefore, is not whether to build a pilot system and throw it away. You will do that. The only question is whether to plan in advance to build a throwaway, or to promise to deliver the throwaway to customers. Seen this way, the answer is much clearer. Delivering that throwaway to custom- ers buys time, but it does so only at the cost of agony for the user, distraction for the builders while they do the redesign, and a bad reputation for the product that the best redesign will find hard to live down.
>Hence plan to throw one away; you will, anyhow.