I think Yoda speaks a little truth here. I know more than anyone that you have to try and sometimes you won't always get the desired result. That said, in life, sometimes you just gotta put up or shut up. And in the movie, at this moment, Luke is whining about something being too hard in his training. Oh Luke...just get it done :)
Do or do not, there is no try.
My kid might be a bit obsessed with Star Wars. And when we gave him full license to be whoever he wanted for Halloween, he decided to be Darth Vader and assigned roles to all of us, including his then unborn brother.