Incorrect software engineering concept

Concept: We have a set of books on how to develop software. The books are full of standards and examples, which can help us solve any problems encountered in software development.
Objective situation: good reference books can undoubtedly guide our work. Making full use of the methods, techniques, and skills in books can effectively solve a large number of common problems in software development. But practitioners cannot rely on books because: (1) in real work, due to the wide variety of conditions, even a fairly mature software engineering specification cannot be applied. (2) software technologies are changing with each passing day, and no software standard can survive. The original secret recipe is delicious in some fields, while it is lagging behind in the software field.

Concept 2: We have the best development tools and the best computers, so we can make excellent software.
Objective situation: a good development environment is only a necessary condition for producing results, not a sufficient condition. If a group of mediocre people have a good environment, it is difficult to ensure that they do not do anything in the north.

Concept 3: If we lag behind the plan, we can add moreProgramPersonnel.
Objective situation: software development is different from traditional agricultural production. If a newbie is added to a project that lags behind the plan, the project may be delayed. Because: (1) New users may encounter many new errors, causing project confusion. (2) It takes time for a veteran to explain his work and exchange ideas to the novice, reducing the actual development time. Therefore, a scientific project plan is very important. It doesn't matter how much advance the plan can be. If we use the "Great Leap Forward" method to go to communism, we will only have the consequences of regressing.

Concept 4: Since the demand analysis is very difficult, no matter how difficult the software is, the software is flexible and can be modified at any time.
Objective situation: the more accurate the requirement is, the less the software is repaired and supplemented. Some requirements are difficult to determine at the beginning, and must be corrected continuously during the development process. The sooner the software is modified, the less it costs. The later the software is modified, the more expensive the software is.