The difference between a good movie and a bad movie for me is that a good movie sets and defines an objective within the first 10 minutes or so, and focuses on the overall purpose of the film, with minimal filler material. If a movie is supposed to be funny, then it should define the direction within the first 10 minutes, usually some awkward situation, and focus on the situation, not the people, or the dialogue. If the comic material is supposed to come from a specific character's point of view, then the movie should focus on that character during the scenes intended for humor. Most movies today are all over the place, with no real definition of what the plot is or where the plot is supposed to end up. It's like a hose that nobody's holding. This is why most movies today suck. They also don't pay much attention to detail.
It's like cooking a steak. Most directors today think you can just throw the steak on the grill, and it will turn out just fine, because everyone loves steak! If you throw it on, and turn it with a baseball bat, then throw a marinade on there halfway through, with the wrong type of spices sprinkled on the surface of the grill, all on the highest heat, then the steak is going to turn out pretty bad. A good director knows to marinate the steak ahead of time, and put the right spices on (and the right amount of spices on) then spray the grill, then turn it on to medium-low heat, and cook the steak, slowly, patiently, carefully, but stay focused, and make sure the steak isn't overdone or underdone. It's a time consuming task, and it can be annoying, but it's worth it in the end. "Even though it was 10 dollars, it was a really good steak. I'm happy I bought it."