Two days ago was the 100th anniversary of the sinking of the Titanic. The “unsinkable” ship sank on 15 April 1912 after hitting an iceberg during her maiden voyage from Southampton, England, to New York City, causing the deaths of 1,514 people – the deadliest peacetime maritime disaster in history.

And 147 years and 343 days ago was the anniversary of the death of Maj. Gen. John Sedgwick, the highest ranking Union casualty in the Civil War. Gen. Sedgwick was killed by a sniper at the Battle of Spotsylvania Court House in Virginia – the deadliest battle of the war with nearly 32,000 casualties.

The deaths from the Titanic as well as that of Gen. Sedgwick could have been prevented.

Both sets of casualties owe their fate to behavior I’ve watched humble many modern-day leaders.

1. Believing you’re invincible. – “Hubris,” from ancient Greek, translates as “extreme pride or arrogance.” Gen. Sedgwick and those in charge of the Titanic tempted fate by an unhealthy belief in their own invincibility. “I cannot conceive of any vital disaster happening to this vessel,” said Captain Edward Smith, commander of the Titanic. “Modern ship building has gone beyond that.” For his part, Gen. Sedgwick was embarrassed by the behavior of his men toward Confederate sharpshooters firing from 1,000 yards away. “What? Men dodging this way for single bullets? What will you do when they open fire along the whole line? I am ashamed of you.”

2. Ignoring common sense. – Fueled by arrogance that it could survive any disaster, the Titanic carried only enough life boats for one-third its total capacity, and with engines “full steam ahead” sped to its demise through a cold front that other ships chose to wait out. In Virginia, the rank and file under Gen. Sedgwick’s command paid healthy respect to the rebel snipers, while the general, judging the bullets no threat at all, continued to walk about in the open inspecting the placement of artillery.

3. Failing to heed warnings. – The Titanic received a series of warnings from other ships of drifting ice in the area, but continued to steam at full speed into a dangerous ice field. “Wonderful thing, wireless, isn’t it?” asked Captain Arthur Rostron to Second Officer James Bisset, having relayed the latest news on the known positions of icebergs several hours before the Titanic hit one. Equally disdainful of enemy bullets zipping all around them, Gen. Sedgwick said, “They couldn’t hit an elephant at this distance.” Just seconds later, he fell forward with a bullet hole below his left eye.

Are you giving healthy respect to threats – inside and outside your organization – that could wreck your plans?

What would a person coming into your organization observe?