Some things happen for a reason, others don't. I would like to think Mark Wahlberg turning down the role playing Captain Kirk's father in Star Trek was a sign of something not happening for a good reason. The role eventually went to Chris Hemsworth who, at the time, wasn't the name he is now. He hadn't yet made Thor or The Avengers and once Thor came around, for the longest time he was referenced as the guy that played Kirk's father in Star Trek.
I don't say this as an insult to Wahlberg or to prop Hemsworth up, I say it because I think it's important for movies to realize that "big star" doesn't always mean "better". Stars can take the attention off the plot, particularly in cameo roles and in this case Wahblerg feels like he would have taken away too much of the attention.
Alternatively, I still remember back when Jennifer Lawrence was cast in The Hunger Games and my frustration as a result. In my opinion I felt the opposite of what I just described would have helped that film, wishing they'd gone with unknowns for the leads and used well known, quality actors around them. Obviously... just my opinion.
As it turns out, I thought J.J. Abrams' casting in Star Trek was spot on, from the top down.