It’s always the obstacles that we don’t even see coming that are the biggest challenges in life.

@Sandeep: Yes, and if we can't see them coming, we won't know how to prepare, but then that would defeat the point of learning and coping.

@ImagineThat: Very true ! So it's exactly ' we don't know what we don't know ' .

It’s always the obstacles that we don’t even see coming that are the biggest challenges in life .

:) no one knows