Calling liquibase from java code, why at the end there is a rollback?

Hi,

i see some examples to how to use liquibase from java code in the forum, for example http://forum.liquibase.org/topic/using-liquibase-directly-from-java     there is near the end a post from Nathan with a code example.

What i don’t understand is why at the end when it closes the connection it calls c.rollback() ?

Thanks for the help.