It comes in many forms. We all experience it.
It can force us to make decisions we'd prefer to not face.
In early July 2009, Eddie McGuire had two dominant football fears. They were named Nathan Buckley and Mick Malthouse, and by late that same month, McGuire, perhaps subconsciously, had prioritised his fears.
Not having Buckley as part of Collingwood's coaching future was a greater fear for the Collingwood president than losing Malthouse.
Nearly seven years on, McGuire is living with a new fear. Was that call the right one?
Sometimes, the best way to understand the now is to revisit the past. And those July 2009 days were heady ones for McGuire.
Buckley, a Brownlow and Norm Smith medallist and six-time best-and-fairest winner at Collingwood, had been retired as a player for just 18 months and had been offered the senior coaching job at the under-siege North Melbourne, which was under new control and had parted with Dean Laidley.
Malthouse, coach of the Magpies since 2000, had made the three previous finals series but not a Grand Final since 2003.
The 2009 season had reached round 17. Collingwood had the Friday night fixture. It defeated Carlton at the MCG for its 11th win of the year.
The next morning at 8am, five men – McGuire, Malthouse, Buckley, Collingwood's CEO Gary Pert and footy operations boss Geoff Walsh – gathered for toasted sandwiches, coffee and orange juice in McGuire's business offices opposite the MCG.
About an hour in to the meeting, Malthouse and Buckley were left together to thrash out McGuire's bold plan for the future – Malthouse to stop coaching the club, no matter what was to happen, at the end of 2011, and for him to then act as a coaching director while Buckley was to take over as head coach.
About 11pm the following Monday, Malthouse signed off on the deal, and an excited McGuire went public the next day. Among his enthusiastic words that day was a link to a speech made in the 1960s by US president John F Kennedy.
"I use the Kennedy scenario. We got to the moon eventually, but a few rockets blew up on the launch pad as well. But that's what happens when you go into a brave new world. It's like anything in life, if you're pulling together forces of nature, nitroglycerine can blow your head off or it can move mountains and it's probably where we are,'' McGuire said.
Collingwood won the next four matches after the Jolimont office breakfast gathering, but lost the final home-and-away round. It lost finals to the eventual grand finalists St Kilda and Geelong.
The Magpies topped up their list in the off-season. Darren Jolly and Luke Ball were added. Malthouse won his third personal premiership in 2010. The following season, in Malthouse's final game, the Pies led Geelong in the third quarter of the Grand Final, but failed to kick a goal in the final quarter and lost.
Malthouse exited. He had always loathed the succession plan he had signed in 2009.
McGuire's intentions were genuine, and in his mind, sound when he made his July 2009 decision. There is no doubt that in his heart he had the best interests of both Buckley and Malthouse.
He will even strongly argue that Malthouse's three disastrous seasons as Carlton coach justified him easing the veteran coach out of the major role at Collingwood.
But only McGuire dared to believe Malthouse and Buckley could work together beyond 2011. Only he thought he could put an old bull in the same paddock as a young bull.
Buckley made a preliminary final in his first season, an elimination final in his second, and missed finals in 2014 and 2015. The side has won just three of its past 15 matches. No matter the spin, this wasn't the plan for year five of Buckley's coaching career.
McGuire has stared down fear his entire working life. And his extraordinary track record will give him confidence that he will fight off this latest batch triggered by the troubles of Buckley, who is contracted to the end of 2017.
No matter what happens in the next two months, McGuire will support Buckley. He will do so because he genuinely believes in him, but also because his own time as Collingwood boss, now into its 18th season, fully depends on it.