Ned Block is professor of philosophy, psychology and neural science at New York University.  His work on consciousness has highlighted how prone people are to miss what is right in front of their eyes.  He discusses this on a Philosophy Bites podcast.

Professor Block mentions that examples can be found on YouTube.  Here’s one.

The particular reason for missing the obvious mentioned by Block, and demonstrated in the video, is that the observer’s attention is distracted.

I reckon that over-familiarity is another reason why people tend to miss the obvious.  This is nicely illustrated in the following lines:-

“Oh, where is the sea?”, the fishes cried,

As they swam the Atlantic waters through;

“We’ve heard of the sea and the ocean tide

And we long to gaze on its waters blue.”

Yes indeed.  Distraction, or over-familiarity, can lead us to miss what is right in front of us, or around us.

God, for example.