Six at the top means

A goat butts against a hedge.

It cannot go backward, it cannot go forward.

Nothing serves to further.

If one notes the difficulty, this brings good fortune.

If we venture too far we come to a deadlock, unable either to advance or to retreat and whatever we do merely serves to complicate things further. Such obstinacy leads to insuperable difficulties. But if, realizing the situation, we compose ourselves and decide not to continue, everything will right itself in time.