(第3空)There is nothing in this world constant but inconstancy. —SWIFT
Project after project designs a set of algorithms and then plunges into cor struction 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 system to throw away, for even the best planning is not so omniscient (全知的)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 ( ) , 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.