Why are some people always late?

We all know someone who never seems to be on time, whether it's to a lunch date or a work meeting. But is there a good explanation for why some people are always late?

The habit of being tardy probably results from a number of factors, including time perception, time management and personality, experts say.

"It is likely that there's a mechanism in the brain that causes some people to be late for meetings because they underestimate the time it will take them to get there," Hugo Spiers, a professor of cognitive neuroscience at University College London and the co-author of a 2017 study in the journal Hippocampus, told Live Science.

The hippocampus is a region of the brain which processes some aspects of time, such as remembering when to do something and how long it takes, Spiers said. Research published in the journal Nature Reviews Neuroscience suggests that neurons in the hippocampus acting as "time cells" contribute to our perception and memory of events, but why exactly some people perpetually underestimate time is unclear.

One factor may be how familiar we are with a space. For the 2017 study, Spiers asked 20 students who had newly moved to London to sketch a map of their college district and estimate travel times to different destinations. While the students' space estimates expanded if they knew an area well, their gauge of travel time contracted with familiarity. "If you're very familiar with a space, you start to discount the hassle it will take," Spiers said.

Related: Why does time fly when you're having fun?

In some cases, people who are late may not factor enough time to complete tasks unrelated to travel, such as getting ready in the morning. Research published in the journal Memory & Cognition suggests that we make time estimates based on how long we think tasks have taken us in the past, but our memories and perceptions aren't always accurate.

"If we have a lot of experience performing a task, we are more likely to underestimate how long it will take," Emily Waldum, an adjunct professor at Campbell University in North Carolina and the lead author of a 2016 study published in the Journal of Experimental Psychology: General, told Live Science in an email. In the study, Waldum found that environmental factors, such as music, can distort your sense of time. 

Specifically, Waldum showed that when doing a general knowledge questions task, some people incorrectly estimated the task's length based on the number of songs they heard playing in the background. Younger adults tended to inflate their time estimates if they heard four short songs compared with two longer songs, something that didn't seem to influence older adults' perception of time.

Another environmental factor may be crowdedness. In a 2022 study in the journal Virtual Reality, researchers asked participants to estimate the length of more or less crowded simulated subway trips. They found that crowded commutes felt like they took 10% longer than less busy rides, which was linked to it being an unpleasant experience.

Personality also plays a role in running late. Certain personality traits, such as reduced conscientiousness, can cause some people to forget tasks that they had planned ahead of time, Waldum said. "Another factor that may influence a person's timeliness is how prone to multitasking they are," she added.

Research published in the journal Advances in Cognitive Psychology has shown that people juggling several tasks at once are less likely to remember and complete other scheduled tasks on time. "The best laid plans can fail simply because we don't have enough attentional resources left to carry them out successfully," Waldum said.

Latecomers sometimes don't perceive themselves as such, Grace Pacie, author of "Late! A Timebender's guide to why we are late and how we can change" (Punchline Publications, 2020), told Live Science. That's because people who run behind schedule tell themselves and others that they can be punctual. "We can be on time when it matters, when there will be negative consequences for our lateness, like missing a flight," Pacie said. 

In the absence of a deadline, however, these people often lose track of time. A 2019 review published in the journal Medical Science Monitor found that individuals with attention deficit hyperactivity disorder (ADHD) can find it hard to process and estimate the passing of time.

Some people struggle to be on time because they deliberately delay tasks. "Lateness can be a symptom of procrastination," Fuschia Sirois, a professor of psychology at Durham University in England, told Live Science. Procrastination is usually rooted in a difficult emotional relationship to the task, Sirois said. 

The difference between procrastination and lateness is that the latter affects our relationship with others, Pacie said. "The same people who perceive us as always being late are the people who matter to us the most, so we can be very hurtful when we say we can be on time when it matters."

So what can perpetually late people do to be punctual for meetings and avoid disappointing friends and loved ones? A self-proclaimed "timebender," Pacie suggested setting alarms and reminders on your phone. Another of her tried and tested tactics is to set pre-event deadlines. "My favorite ruse is to offer somebody a lift," Pacie said. "It means that you arrange to meet them at a sensible time."