而且就算一个问题被确认了，需要重新设计，这个新的设计还是需要测试。

And even once a problem is identified, a solution needs to be designed, and that may need testing too.

youdao

软件产品中的内存问题是非常难以修复的，因它常常需要做很多的重新设计。 因此未雨绸缪将省下后期的很多工作。

Memory issues are very hard to fix when you are in production since they often require a lot of re-design, so a penny spent in the early stages will save a lot of pennies later.

youdao

需要对问题进行修复，需要添加新功能，需要重新设计接口，还需要删除不需要的功能。

Bugs need to be fixed, new functionality added, interfaces redesigned, and unneeded functionality removed.

youdao