Well this movie suffers from the primary problem of most others like it; they barely introduce us to a cast of characters before they start bumping them off, in some cases before we even know their names lol. Also adding on to this issue of emotional disconnect nearly every scene in the film is shot from the POV of a static CCTV camera so it is like watching a documentary about an event we don't really care about featuring a cast we know hardly anything about.
It's amazing to think that people actually read (?) these scripts and then think it's a good idea to finance their production into a film.