I think Ghaddafi's soldiers defected because he ordered them to shoot up a non-violent protest in Benghazi, killing at least 500 unarmed civillians. That's when

I think Ghaddafi's soldiers defected because he ordered them to shoot up a non-violent protest in Benghazi, killing at least 500 unarmed civillians. That's when the protests turned into an armed insurgency, and Ghaddafi's supporters began leaving to join said insurgency.