Your learning curve is greatly reduced because you get to leverage the “knowledge” of a coach. Imagine if someone took 10 years to accomplish something but it only took you two years to accomplish the same thing. You are afforded the advantage of learning the shortcuts and secrets to get to the end goal. What we can easily see is that knowledge transmission is definitely a major aspect of mentoring and coaching. 

Probably one of the most critical aspects of mentorship is that it provides a structure for accountability. Whenever a protégé has goals to achieve, they often subject themselves to their mentor to help them stay focused and on the path. 
The mentor is there to ensure that accountability can take place and goals can be achieved.