unless的问题我一直没搞明白

比如说 not .A unless B => A->B（这个应该对吧？）

那么，问一句话的解释：

the reason is that the bottlenecks and delays cannot be eliminated unless all work is done right the first time ( OG 11-110 )

根据前面那个公式的话，不是翻译成“如果瓶颈和延误被消除，那么所有的工作在第一时间都能做好”

这个翻译对吗？总觉得非常奇怪啊~~

应该是这个意思,"瓶颈消除－－>第一时间正确"那么逆推回来就是＂第一时间错误－－＞有瓶颈＂，

其实也就是把答案Ａ给翻译过来了，可我很不明白题干问的是假设，可Ａ是从文章的最后一句话里直接推理出来的，怎么就对文章构成了假设呢？？

110. "Fast cycle time" is a strategy of designing a manufacturing organization to eliminate bottlenecks and delays in production. Not only does it speed up production, but it also ensures quality. The reason is that the bottlenecks and delays cannot be eliminated unless all work is done right the first time.

The claim about quality made above rests on a questionable presupposition that____

(A)           any flaw in work on a product would cause a bottleneck or delay and so would be prevented from occurring on a "fast cycle" production line (答案)

我觉得那句话的意思是：

除非所有事情都在第一时间做好，否则无法避免瓶颈

right, "do the job right at first time" 是必要条件 （而非充分条件）