Many potential sea accidents are avoided through sheer blind luck. But luck is never to be relied on.
Early on the evening of March 6 1987 the ror-ro ferry Herald of Free Enterprise set out for Dover from the Belgian port of zeebrugge. <ref>http://www.independent.co.uk/news/uk/home-news/zeebrugge-ferry-disaster-ms-herald-of-free-enterprise-uk-30-years-on-maritime-tragedy-killed-a7583131.html</ref> Just 23 minutes later she rolled over within the space of two minutes, killing 193 people.
It's a simple story. The bow doors were open. The stern doors were open. She sailed anyway to keep to schedule.