In the film industry, the answer to what makes a film good is subjective to the audience however there are certain aspects and elements of a movie that can make it great to watch. 

First off is the story, a great film needs to have a great story and for anyone to enjoy it it must be engaging but also allow the viewer to connect with it. I believe that whilst the story must be engaging it should also show true insight to human experience too allow the audience to deeply connect with it. 

Second is the cinematography a great director and dop is needed to allow the story line to really flourish and fester with the audience for example use of close ups in tense and suspense filled moments or wide angled shots in moments of isolation and loneliness 

Another key aspect of a good film would be the cultural impact. Movies such as Taxi driver and The Joker are good examples of this as they shedded light on mental illness and loneliness which gave the movies are real sense of emotional connection with a lot of the audience. 

Casting also has a significant impact on the resonance of the film since the perfect actor for the perfect role will allow the movie to seem more realistic which is one of the biggest goals for a filmmaker, the movie The shining is the perfect example of this since the casting of jack Nicholson for jack Torrance fitted him perfectly and made the film an amazing watch with extremely realistic moments and amazing acting, especially when featured with Shelly Duvall as Wendy Torrance. 

Last of all is technical innovation, many great films are remembered for using cinematic devices in inventive ways which pushed storytelling forward and experimented with artistic conventions. This could be through the cinematography, editing, music or any other expression of technical creative decisions. This could be the dark lighting that set the tone in The Godfather, or the match on action cut that transported the story 1000s of years in 2001: A Space Odyssey. 

When watching a great film, more often than not, nothing feels out of place or awkward. The audience just gets sucked into the story. We do not question anything from a tonal point of view or point out technical flaws. This is the sign of a polished technical style.