The Check List for Reliability

A lot of the content in waf is around explaining and providing guide lines for different aspects. But then on each sort of main topic, you have a check list. And i'm a bitn sure on the check lists. For example, for reliability, theye's a checkList. Does it mean that i have to check off each item, or can i just speak and choose the ones that i feel are the easiest to achieve? So how do you approach the check list? And at what check lists do we have or reliability? Are they elements that all of those have to be ticked off? Or depending on the situation, do you apply an adapt based on the check list