In a half-hour, you can easily sketch out a set of requirements that will keep even the best programmer busy for a month. The system should be able to identify where any part is from the time it leaves the vendor until we retire it from service. The system should be able to identify and neutralize a threat in .003 seconds. Any employee can identify which seats are available at any time. Note that these describe the goal of the customer but leave a lot unsaid.
Requirements do because they specify the destination rather than the journey.
It is not enough to write down the requirements. The customers must review each change and sign off on it. Integrate the Design Software is documentation, descriptions, and sets of instructions. At its very least, software documents what instructions that you have given to the machine. Make the code and the design one.