What led to the failure of NASA’s mission?

NASA’s first dedicated mission to measure carbon dioxide from space has failed following a rocket malfunction.
    (28) Officials said the fairing—the part of the rocket which covers the satellite on top of the launcher—did not separate properly. Data indicates the spacecraft crashed into the ocean near Antarctica. (29) The Orbiting Carbon Observatory was intended to help pinpoint the key locations on our planet’s surface where CO2 is being emitted and absorbed.