While doing my research and some readings, I have learned that the star system is considered as one of the most controversial contributions of film to the long history of acting. It is the method of exploiting movie stars in Classical Hollywood Cinema. The agency or studios would select and glamorize promising young actors to the point where they create personas for them, inventing new names and even changing their backgrounds for them to fit the 'star' bubble.
Star system emphasize more on the image rather than the acting, although discreet acting, voice and dancing lessons were all a common part of it. I've also read that women were expected to behave like elegant ladies and they always have to dress up in a very stylish way while Men were expected to be seen in public as a total gentlemen, in that way people will recognize them as the perfect celebrity.
The studio executives and the staffs helps the actor to build a star persona. They work together to avoid things that would damage the image of their actor. They are also the ones in-charge in making up dates between male and female stars to stir up publicity. In show business, it is essential that the actors are well known because it will determine how long they would stay on the spotlight. If you want to be a total star, you have to be publicized. And their main goal is to help their actor boost its popularity. In short, it is their responsibility to protect the actor by covering up everything that would make him/her fall down.