Resist making statements such as “The system shall be user friendly”. It is entirely insufficient. The non-functional requirements document template breaks the section down into seven subsections and prompts for completion of each section. Be specific about the mechanism by which each aspect will be met. For example, in the section ‘Learnability’ say whether the user is expected to learn how to use the system by looking up the help or using a tutorial or whether the system can be put into a ‘learner mode’ whereby it guides a learner user through a use case by offering detailed prompts at every step. If there is to be no documentation at all and the system is to be learnt from the developers demonstrating it to the users, then say so.