Russian Cargo Ship Docks At ISS On Second Try
FleaPlus writes "Following up on a story from a few days ago about an unmanned Russian cargo ship's initial aborted attempt at docking with the International Space Station, Space.com reports that the vehicle made a second pass on July 4, which succeeded. Russian engineers believe the initial abort was triggered when the (normally reliable) Progress spacecraft detected interference between a remote control system on the ISS and Progress's camera. It successfully docked on the second try by using the autonomous system instead."
wow.. shame no-one actually answered your question..
Short answer:
http://quantumg.blogspot.com/2010/07/jeff-greason-answers-why-humans-in.html
Longer answer:
http://quantumg.blogspot.com/2010/06/why-space.html
How we know is more important than what we know.