Wabi sabi the Japanese worldview of Raku finds beauty in perishability, transience and imperfection of things.  Over time there are many beautiful imperfections that make things and humans unique. Raku ceramics are not just objects, they are a continuous process that is connected to the elements of nature.  They are survivors of a torturous process as they manage to survive under extremely harsh conditions in almost volcanic temperatures.  Repeated thermal shocks they undergo are capable of breaking them.  That's where their beauty lies,  in their imperfections, in their cracks, in the signs of their existence.
In the freedom they give us to surprise ourselves with the unexpected.