Oh, that's why.
The plot revolves around a loser boxer, Davey, who sees his neighbor Gloria, a dancehall girl, attacked by her boss, who is obsessed with her. Davey rescues her from his abusive boss, Vincent, but the sleazebag is undeterred and kidnaps her, and attempts to kill Davey, only to mistake Davey's manager for him. Davey is blamed for the murder by the police and has to clear his name while rescuing Gloria. It's a pretty good noir set-up, but the execution falls flat.
For all that, though, Kubrick's talent for scene composition is brilliant and his choice of locations inspired. He reportedly only had a budget of about seventy thousand dollars to make this film. His solution? Make the city of New York his real star.
A few screenshots to illustrate:
Seeing it again, I remember why I kept the file. Think I'll keep it around to rediscover in another six or seven years.