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English writer and theologian William Penn once famously said, "Time is what we want most, but what we use worst." Most likely, he meant that most of us squander the time given to us, as though it’s an endless resource. But, for the sake of this topic, let's also apply it to those of us who simply can't manage time properly.

We all have those friends who are shockingly, chronically late to everything—and those who are always early. (I'm the latter, and it seems to be equally annoying to the people in my life.) The question is why are we this way and how can we learn to co-exist? There are many reasons that contribute to how we manage time, and they of course depend on a variety of individualized factors, but one theory floating around is actually how full or empty we see the proverbial cup.

From an article posted on University of Southern California's School of Psychology site, it all comes down to our bias toward optimism or pessimism. For the late arrivers, it's called the planning fallacy. "Psychologist Daniel Kahneman and colleague Amos Tversky introduced the concept in 1979, defining it as 'the tendency to underestimate the amount of time needed to complete a future task, due in part to the reliance on overly optimistic performance scenarios.'"

In other words, they might feel it will all "flow" as it's supposed to, so there's no need to plan ahead. "Psychologists call this mindset 'optimism bias.' While being optimistic has its benefits, such as an improved state of well-being, getting caught in the constant cycle of optimism bias can cause issues at work that impact productivity."

In a piece for The Decision Lab, author Kira Warje,further explains, "Whether it's building a house, launching a product, or studying for an exam, people tend to create overly optimistic timelines and budgets. This happens because we focus too much on the best-case scenario and ignore relevant historical data or potential setbacks."

She also explains the notion that an outsider would estimate time differently, writing, "Interestingly, the planning fallacy only affects estimations about one’s own task completion times. Outside observers tend to lean in the opposite direction, overestimating the time needed to complete a task."

As for the early-arrivers, we perhaps overestimate the amount of time something will take. Often this is driven by anxiety in general, but to couch it in similar terms, this would be a pessimism bias.

In her article for VegOut Magazine, culinary writer and chef Maya Flores she shares eight traits that people who often arrive early share. One is "They have a physical discomfort with rushing." This, at least for me, is so true. And although early-arrivers often tend to pessimistically assess a situation, we are actively trying to avoid feeling the discomfort that comes with rushing.

A person drives frantically. Giphy GIF by HRejterzy

Another trait Flores shares is, "They have a complex relationship with control." This doesn't imply they're "control freaks." Flores writes, "They've identified what's actually within their power (when they leave, how they prepare) and released the rest. That need for control over their own state—their calmness, their preparation, their transition time—remains non-negotiable."

And if one digs even further, there may be deep-seated reasons for it. "Many early arrivers have a story: the time they were devastatingly late for something important, a chaotic childhood where nothing started on time, or a formative experience of keeping someone important waiting. They're not necessarily traumatized, but they've decided: never again."

In the Reddit post "Is anybody else chronically, pathologically EARLY?" there are well over 400 comments, many of whom back up the theory that this began in our formative years. One commenter writes, "My mom was 10 minutes late for everything my entire life, and I’ve been mortified by it for as long as I can remember. It wasn’t a crazy amount of time, but it was for things you just can’t be late to, weddings, doctor’s appointment, jury duty, that kinda thing. I’m always early because of her haha."

A clock does its thing. Giphy GIF by MOODMAN

Another shares, "Same here. I spent so much time experiencing consequences for other people’s lateness or waiting endlessly to be picked up as if the person responsible didn’t know what time things ended, so I have just chosen the opposite. I’m rarely dramatically early, but I can’t be late to things that have a firm start time."

Then there are those who have mastered the art of being "exactly on time." In an article for The Expert Editor, author Lachlan Brown, discusses these folks, who retain traits from both groups. "They possess a heightened sense of responsibility" and "they value structure and routine." If one has these characteristics, without the anxiety that often comes with them (at least for us early birds), they can land somewhere in the coveted middle.