Many of history's biggest tragedies were preventable disasters. Some started small and escalated quickly, and quite a few were human-made disasters caused by flat-out avoidable error. Even the consequences of many natural disasters could have been mitigated if people had just listened to warnings and paid attention.
Alas, people never learn - nor pay attention - and as a result, loss of life and destruction are often inevitable. These disasters that could have been avoided may have you thinking twice the next time you scoff at a meteorologist's warnings.