Moon Seong Mook, a South Korean analyst and former military official, says that the North would gain valuable knowledge even from failed launches as it continues to improve its technologies for missiles: "They could be testing a variety of things, such as the thrust of the rocket engine or the separation of stages," Moon said. "A failure is a failure, but that doesn't mean the launch was meaningless."
North Korean ballistic missile tests are banned by the United Nations because they're seen as part of the North's push for a nuclear-tipped missile that can hit the U.S. mainland.
