You’ve seen it in dozens of films, mostly in black and white. Somewhere outside in the dark of night, three guys take out cigarettes. One of them strikes a wooden match. The match flares up from the phosphorous in the tip and then settles down to a steady yellow flame. The guy with the match lights the first guy’s cigarette, then the second guy’s, but snuffs out the match and tosses it away without lighting his own. The dialogue here rarely varies. He makes some comment about three on a match is a good way to get shot by a sniper and then lights his own cigarette with a new match.

Some say this superstition got its start in World War One, when armies fought wars with simple weapons. Most of the fighting was men in deep trenches shooting across a no-man’s land at each other. A lighted match is easy to see from a distance at night, and so is the guy lighting it. An enemy with a rifle would see a cigarette being lit, and within a few seconds could sight in and get off a shot. It was widely held that two guys lighting cigarettes with one match could do so safely, but not three. 

So three is an unlucky number, right?

Faced with large numbers of battlefield casualties arriving en masse, Army doctors needed to quickly determine which cases required immediate attention, which could wait and which were too far gone to save. There were never enough doctors, so their skills had to be rationed so that the largest number of lives could be saved.

Top priority was given to soldiers with a good chance of survival if they were given immediate treatment by a doctor

Soldiers whose wounds were not life-threatening could be put on a temporary hold and watched over by paramedics and nurses. Some soldiers were so badly wounded that they would not survive no matter the effort of the doctors. Medics could do no more than ease the pain of these tragic casualties for the few minutes they had left. My father was a young battlefield doctor during the Korean War. Every day, he had to make do-or-die decisions in terrible conditions under extreme pressures. For the rest of his life, he thought of things as needing to be done immediately, when time permits, or not at all.

So are threes a bad thing or a good thing?

Goldilocks enters a family’s house uninvited when she sees they are not at home. She eats their food after complaining that some of it was too hot and some was too cold. She sleeps in their beds after complaining the others were too hard or too soft. In the familiar tale, when the three bears came home, she ran away. In an earlier version, the bears killed the home invader.

Three little pigs built three little houses. When the Big Bad Wolf administered the Huff and Puff test, the house made of straw collapsed instantly. The house made of sticks fell apart a moment later. Only the house made of bricks survived. The lesson was that things made with better materials and superior craftsmanship last where things made cheap and easy don’t.

The processes of assigning of things to one of three broad categories is called triage 

From its beginnings in emergency medicine, triage has been a useful way of prioritizing large numbers of anything. We can look at any set of actions and decide which need to happen first, which should go next, and which can wait until later. We would want to fix the plumbing leak in the shower before shopping for tiles, for example, as I wrote about in Your Shower Is Leaking.

The origin of the word triage

Some say it was the term used to describe the sorting of coffee beans. Others say it comes from sorting wool. Either way, it was a broad classification scheme that did not get bogged down in the details. Whether it was beans or wool or something else, the French adopted the term to mean sorting a group of objects by assigning them to one of three broad categories.

When you learn to think in threes, you find examples everywhere

• You can choose a large, medium or small cup of coffee or an ice cream cone without knowing exactly how many ounces or grams.
• You can dicker over grade point averages but you’re better off thinking of students as passing, failing, or honors.
• Freud’s id, ego and superego.
• Rock, paper, scissors.
• The Good, the Bad, and the Ugly.
• Red, yellow and blue – the primary colors from which all others are formulated.
• Cold, hot, or comfortable? The middle ground is preferred by most.

No one has unlimited resources 

Everything can’t go first. Efficiency experts know you get more done if you begin by sorting your tasks into Now, Soon, and Later. Decision makers who can accurately determine which activities are crucial and which can wait until later easily outperform competitors who don’t understand how to set broad priorities first.

Triage your triage

When you find there are too many things in your highest priority pile, triage them. Split them into three more piles after you have obtained a more detailed understanding of the resources required.

Want to read more articles like this? Click here for free, no-ad, no-tracking access to the hundreds of articles David has written each week since 2016. He covers lots of topics, always showing there is more to things than meet the eye.