Software estimates have never worked and never will
Since the dawn of computing, humans have sought to estimate how long it takes to build software, and for just as long, they've consistently failed. Estimating even medium-sized projects is devilishly difficult, and estimating large projects is virtually impossible. Yet the industry keeps insisting that the method that hasn't worked for...
为什么「给软件开发估时」这事不靠谱。因为软件开发很大一部分是与未知打交道（比如一个很小的 Bug，可能需要好几天才能找到头绪；一个小改动可能影响很多模块；很多边缘场景要考虑等等），未知的事物如何估时？
The fundamental problem is that as soon as a type of software development becomes so routine that it would be possible to estimate, it turns into a product or a service you can just buy rather than build.