Triple Frontier is a hard target. What it lacks in creative writing or compelling characters it makes up for with a brutal tension that carries it through it's 2 hour 5 minute runtime. This tension is developed in part by desolate locations and situations mixed with what feels like excellent chemistry between most of the main cast.
What brings this movie down is a lack of character development or growth throughout the film. Main characters are introduced and givin a general back story if any at all, and then do not have any dramatic arc or depth to their journey throughout the rest of the film. The movie kind of just grits it's teeth and pushes past anything other than service-level emotions and reactions.
Also, and this is kind of nitpicky, Triple Frontier uses too much pop music. Instead of a dramatic or emotion swelling original score the film defaults to Metallica or CCR for dramatic effect. I think this is kind of a waisted opportunity on the film's part.