"Most people, for most of the time, are starved on feedback and are left to operate on the basis of 'no news is good news"
Peter Honey
Giving feedback is an effective management and influencing tool to use with others. The E.E.C. model is one way of formulating the feedback:
Example
Use specific behavioural examples e.g."George, I noticed you've made at least 3 personal phone calls today, one lasted at least 10 minutes" rather than: "you're making too many personal phone calls". Specific evidence is very powerful.
Effect
What effect does the behaviour have on you, the team, the business or (probably most important) the organisation's reputation in the eyes of customers. In George's case it means that he is wasting time and distracting the rest of the team. If the effect is not mentioned then George may think we're not committed enough to ensuring a change in his behaviour.
Change
The change in behaviour you would like to observe in George. In this case you might say: "I would appreciate it if you could make your personal calls outside work time. Obviously the situation is different if it's an emergency"
E.E.C. can be used for positive feedback too. The change could be about maintaining the good behaviour or even consider ways of doing it even better. However this can run the risk of being seen as a 'back handed compliment': "I didn't something good, but she still wants more. I can't win!