Might catch a lot of hate for this given the love for this movie in other subs, but I'd say that most recently Godzilla (2014) had the most wasted potential. Bryan Cranston, hot off of the success of Breaking Bad, was bait-and-switched for Aaron Taylor-Johnson. It's made even worse by the fact that Cranston's character is the only character with any sort of motivation to speak of and Taylor-Johnson's character is this completely stoic military officer. The script has a hard time making me believe he cares more about his family than a random Japanese kid on a subway.

I've heard praise for the teased fights in Godzilla (2014) saying that it built tension for the final fight, but I honestly thought it diffused a lot of the tension. By cutting away from the fights, we miss the opportunity to see what types of attacks each monster could execute and what their weaknesses are (or if they have weaknesses at all). I'm not asking for Godzilla to bust out atomic breath in the first half of the movie, but some basic attacks to establish the aforementioned would be nice. By stripping the audience of the opportunity to see those outcomes, we can never see how the military adjusts their plans because of what they saw during the fight (which is also frustrating as much of the screentime was devoted to military men talking about plans that would ultimately fail against the monsters). Furthermore, by cutting from one scene where two monsters are fighting to watching Godzilla swim to another location, while the Muto makes its way to Vegas, we lose a sense of what's going on. Why were they separated? Why don't they have any injuries from that fight? Were we even supposed to care about that city that they were fighting in? Skipping over the outcomes of these fights also left me with the impression that the consequences aren't very important (which doesn't seem like the best thing to do in a monster movie).

Before the final fight even happens, I can't invest myself in it because 1) I'm expecting the action to cut away yet again and 2) the movie has given me the impression that the consequences of the fight is unimportant. In the actual fight, we see injuries take place (Muto scratching Godzilla's neck, Godzilla biting Muto's shoulder, etc.) but none of them really affect the way they fight. The audience is essentially left with a fight that's determined solely on which monster can land a more powerful blow. It doesn't really feel all that worth it to wait nearly the entire runtime for a fight that comes down to one move.

TL;DR: Godzilla could have been a tense monster movie lead by a four-time Emmy winner. Instead, it's a monster movie lead by Aaron Taylor-Johnson and inadvertently diffuses its own tension.