You decide not to board because you're afraid.
This means you lose pretty much all the money to your name (there is no refund option) and have to either make the long journey home with absolutely nothing or keep residing in Libya. It's getting very lawless in Libya - armed groups allied to Libya's rival governments are locked in a battle for control of the oil-rich nation. There is also no migration or asylum system making you particularly vulnerable. In addition to that, there is growing hostility towards refugees and migrants coming from Libyans and attacks are taking place, however there is no legitimate police force to report incidents to.
