Why the ferry was allowed to sail will know doubt need to be looked into as many people will be very angry at this...
The ferry left in calm seas on Friday, with no severe weather forecast for the trip. Mid-way through the typhoon changed direction, and with the ships engines failing, it was doomed.

I wouldn't even trust an Asian ferry on calm waters, if I had to go on one, I'd pack an inflatable life raft in my luggage.