The second is an iteration process that applies the nested map to each of the elements of the input array.

第二个是迭代过程，将嵌套映射应用于输入数组的每个元素。

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Failure is a necessary part of the innovation process because from failure comes learning, iteration, adaptation, and the building of new conceptual and physical models through an iterative learning process.

FORBES: Creating An Innovation Culture: Accepting Failure is Necessary