This is because there's so much to consider; if it's a narrative film (the kind this blog will celebrate) there's the story or plot, rarely both. As either an extension, reinforcement, enhancement or contrast to the story or plot there's the editing, camera direction, sound and the myriad elements which make up the visible universe of a movie (that's mise-en-scene for snobs).
There's also the inexplicable phenomena of performance involved which often renders you a crippled thinker. An innumerable amount of variables are always at play so that an attachment to one particular detail could distract you from another.
But the information is there. Intended or not, every cinematic decision has implications. What a movie manages to convey through its form is separate from one's opinion of the movie itself. This is the point to remember; your opinion actually counts for very little.
Surprising as it may be, there's measurable ways to more accurately evaluate the worth of a movie. Traditional film reviews lean too much on personal opinion as opposed to objective cinematic observation and analysis. It's rare to uncover a film review that addresses the film in cinematic terms. More often the review is a condensed summary of the story followed by an approval or a dismissal.
The good news is that we don't mourn here. Regardless of critical inadequacies or visual illiterateness, the cinematic information and subtext is always present in a film and if anything, it's us who aren't looking hard enough.