Here is a Wabi-Sabi story (from Koren's book again) about Rikyu's
"entrance exam" before being admitted as a student of the
famous tea master Takeno Joo.
Rikyu was asked to clean Joo's leaf-strewn garden.
First he raked until the grounds were spotless.
Then, in a gesture pregnant with Wabi-Sabi overtones,
he shook a tree trunk, causing a few leaves to fall.
Wabi-Sabi, as evidenced here, is clean but never too clean or streile.
Virtually the sams anecdote is told wherin Rikyu is the master
and his son the aspiring student. In this version it it Rikyu
who shakes the leaves from the tree as a reprimand to his son,
who has rendered the garden grounds completely leafless.