Why do (sometimes) seemingly unimportant moments really stick as detailed memories, and some seemingly very important moments are hard to recall?

Question

At times, apparently mundane memories are really easy to recall, and moments you think ‘I want to remember this in detail, even gonna do an eye-camera pan of the scene’ don’t come back that easy. Why?

In: Biology

Answer 1

The first ELI5 I enter – no answers. Something I won’t forget! Maybe moments that seem simple are unique in a way after all.