The Recipe Book is Always Incomplete
When it comes to dealing with people, there are basic ingredients but you and the circumstances determine the recipe. What will work for one "chef" won't for another and, of course, customer tastes will vary.
This is where experience pays off. It will guide your formulations and, if you are fortunate, will eventually create a valuable form of intuition. That something may feel right (or wrong) at a particular point won't be because of happenstance but instead will be the product of informative experiences.
In human relations, a recipe book only works up to a point. Making decisions is one of the ways we acquire judgment. That process often involves making mistakes.