Brevity; many picture books for children have 150 words or less. Ten last sentences
from some of my favorites (in no particular order):
The next thing you know, you're flying among the stars.
--Tar Beach, Faith Ringgold
"You must do something to make the world more beautiful."
"Alright, " I say. But I do not know yet what that can be.
--Miss Rumphius, Barbara Cooney
It wasn't long before the first birds came to the new, beautiful island.
--Rotten Island, William Steig
He is very happy.
--Ferdinand, Munro Leaf
...and it was still hot.
--Where the Wild Things Are, Maurice Sendak
Though I've grown old, the bell still rings for me as it does for all who truly believe.
--The Polar Express, Chris Van Allsburg
...it was also the first day in her life that she walked alone, without holding
either her mother's or father's hand.
-- Umbrella, Taro Yashima
After breakfast he called to his friend from across the hall,
and they went out together into the deep, deep snow.
--The Snowy Day, Jack Ezra Keats
And the Five Chinese Brothers and their mother
all lived together happily for many years.
--The Five Chinese Brothers, Claire Huchet Bishop and Kurt Wiese
And it would murmur, good night.
--And If the Moon Could Talk, Kate Banks