Project  after  project  designs  a  set  of  algorithms  and  then  plunges  intoconstruction of customer-deliverable software on a schedule that demands delivery of the first thing built.

In most projects, the first system built is （ ） usable. It may be too slow, too big , awkward to use, or all three. There is no （ ） but to start again, smarting but smarter and build a redesigned version in which these problems are solved. The discard and （ ） 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. Where a new system concept or new technology is used, one has to build a syste m to throw away, for even the best

planning is not so omniscient (全知的) as to get it fight 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 （ ）.  or to promise to deliver the throwaway to customers. Seen this way, the answer is much clearer. Delivering that throwaway to customers buys time, but it does so only at the （ ） of agony (极大痛苦) 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.