I prefer explanations

Not everyone likes explanations. Some of us like thinking about what could have actually caused this. For me, a lack of explanation keeps the movie inside my head longer, because I try to figure out what really happened. I look for possible clues too. It is more fun that way.

There was actually a sort of explanation early in the story, from the conspiracy nerd working in the shopping centre/mall. There were no further explanations in the movie, which was a bit odd, but I kind of suspected that there would be no real explanation, as it was that kind of movie.

Well like the walking dead, you dun have to know how or why it happen.

Most explanations would only be lame.

What kind of aliens/demons/virus etc can't infiltrate a building?

It's actually better writing because avoided the pointless exercise of explaining things, scientists and army generals in a canvas tent, shoulders hunched, palms on the table (except for those stroking their chin), inventing a new gobbly-babble to explain things in audience-intelligence-level terms, etc.

That's not what this film is about — it's about the people in it and how they react, cope, reason — and getting us on the edge of our seats, which it did fine for the most of the film (and would have done less of with a large dose of explaining).

That said, the last act or two of this film took a point off of my score. It just wasn't that great of an execution, with 15 minutes running through lots of shaking trees and bushes, LOST style. In other words, the last minute thrills were not as strong as they should have been for the final action act (which should always have the BEST suspense and thrills for this kind of film).

I agree completely. The "unexplained story" has always struck me as lazy and gimmicky. I remember this kid in my creative writing class in high school who always wrote these lame stories about mysterious unexplained events. The teacher loved them, but it seemed to me there was no thought put into them whatsoever beyond the original "unexplained phenomenon".

A story that has things happening for no reason just isn't as memorable as a story that slowly reveals the cause of the events and allows you to make guesses along the way.

It's the work of lazy cheaters and I always feel frustrated at the end of them.

What did you need explaining? Because it was a pretty simple movie to understand. Only idiots didn't get it.

It's unbelievable that people need to be spoonfed plots now.