What does "lark understands" mean?

Larks understand a truth: if you want to fly high, you can't aim too low. If you only keep your eyes on the canopy, you will never soar in the blue sky and white clouds.

This article is an intriguing fable. Through the dialogue between larks and different objects, the author uses repeated techniques to bring the images of sparrows, cocks, quails and other people who are not ambitious and willing to be mediocre to life, and at the same time embodies the great ambition of eagles to forge ahead and soar in the blue sky. The lark's curious and thoughtful attitude towards Almighty God inspired us.

The original text of the lark understood:

The lark saw sparrows jumping on the branches all day and asked, "Mrs. Sparrow, why don't you fly higher?" "

The sparrow glanced sideways and said, "Am I still flying high?" Look at this rooster! "

"Uncle Rooster, why don't you fly higher?"

The rooster proudly took eight steps on the roof and asked, "am I still flying high?" ? Look at quail! "

"Why can't you fly higher? Sister Yu. "

Quail struggled to fly over the top of the grass and proudly said to the lark, "Can't I fly high?" Look at this toad! "

Later, the lark met the eagle and asked him, "Uncle Eagle, why are you flying so high?" ? "

"No,no." The eagle said modestly, "I am far from the blue sky!" "

"Oh, I see!" The lark blinked and thought, "Whoever wants to soar can't set his goal too low;" If you only look under the canopy, you will never be able to soar between the blue sky and white clouds. "