The pilot reported that while on approach for landing, he noted wind direction changes and turbulence. After touchdown, the airplane bounced a couple of times and he decided to go around. The pilot stated that the airplane initially had a positive rate of climb but suddenly it lost altitude near the end of the runway. The airplane touched down, ran off the runway surface and travelled down a steep embankment. The airframe and wings were substantially damaged. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.