Because that is the the part of software engineering which needs the most experience and general knowledge. There is no way around it. After all you need to kno

Because that is the the part of software engineering which needs the most experience and general knowledge. There is no way around it. After all you need to know the constraints around a system before even building it and that is only possible if you have seen it before. It can help to study others people work before starting a project in a similar domain.