Question: What happened that was good but it didn't go to plan

Richard Moss answered on 18 Mar 2016:

Many years ago the Russians had their own space station, Mir, and they tested a new automatic docking system. It failed and crashed into the station, making a hole in the wall. In the end the crew had to isolate that module and it was never used again. Everyone learned that we must test new equipment and techniques fully before allowing them to used in space!