Michael Dorn; one smart Klingon

Michael Dorn began playing the character of Worf  in Star Trek; The Next Generation in 1987.  He never decided he needed to do Shakespeare or 'expand' his portfolio. 

He continued to portray Worf through the entire series of STNG, into the movies,  then, onto Deep Space 9.  

Unlike others who seem confused about roles and their position as actors, Michael Dorn grasped the fact that has escaped almost every other actor in a popular television series;
stick with what works, because that will insure you work.

To be Worf requires quite a bit of make-up, hence Michael Dorn could be sitting next to
you at a sporting event, and you might not realize it.  He had all the fame and recognition in character, all the comfort of privacy outside of it.

He could become a pilot, he could enjoy his life, and he didn't have to wonder where his next pay check was coming from.

Michael Dorn is unique. So many popular television characters grow enormous egos and decide they want more money or have 'creative differences' with writers, or need to expand their repertoire and wind up has beens never having really made it.

Outside of a narrow band of fans who watch that particular show they are, nobody.

Few actors appearing on television get  fantastic movie offers where they go from the small screen to the large one with great success.  For every George Clooney or Denzil Washington there are thousands who fade into oblivion.

A few may take the show with them when they leave, making any kind of sequel impossible.  The show goes off the air  and is soon forgotten save for a handful of fanatics.

Other ego driven performers are replaced by  actors who create as popular, if not more popular characters.  There is no way back for the fool who leaves the successful show for nebulous big breaks. 

Although Michael Dorn has played other characters besides Worf, they are small shrug away roles.  As he has never made being Worf a problem, he continued to work. 

No doubt, if called upon to become a Klingon again, in a movie or another Star Trek version, he will do so, because he never made it a problem.