[ Policy ]

A definition for ‘policy’ is  ‘a deliberate system to guide decisions and achieve rational outcomes.’   

So, taking that definition apart, in the context of an organisations’ documents: a policy is a deliberate document.  It shouldn’t be hidden or mysterious or hard to understand. 

A policy is there to guide decisions:  this is probably not appreciated enough when we read or develop policies.  It should help the person subject to that policy to make good decisions. 

And finally, policies help achieve rational outcomes. There’s some hidden weight to that.  The purpose of a policy is the outcome being rational, and achievable.