Because Susanoo—who had been instructed to rule Unabara (the sea)—kept crying, saying he wanted to go to the land of the roots (the land of Izanami), he was finally expelled by Izanagi.
海原を委任されたスサノオは、イザナミのいる根の国に行きたいと言って泣き続けたためイザナギによって追放された。