Why people drive under the speed limit

It can be infuriating when the motorist in front of you is driving under the speed limit.

Beyond showing hand gestures and beeping their car horns, motorists can’t really communicate with each other. This lack of communication means that you can only make assumptions about why someone is driving too slowly.

When we become frustrated and impatient, we tend to assume that slow drivers are being willfully ignorant of those around them. We may even come to the conclusion that they are intentionally trying to annoy us.

Although that may be true in certain cases, there are other possible reasons why they are driving under the limit.

Note that many of the reasons listed below aren’t intended to be excuses. In fact, some of them are considerably more dangerous than simply being ignorant.

Mechanical issues

Sometimes, a motorist will experience mechanical issues with their vehicle. This can happen while they are en route to their destination.

They hear an unfamiliar sound emanating from their car and instinctively slow down to minimize the damage. They may not even have a choice in the matter, as many modern engines will automatically reduce┬átheir power and go into “limp mode” when they detect an issue.

Some people drive slowly due to anxiety

Learner drivers and elderly drivers can feel anxious while driving.

Learner drivers often feel worried about traveling at high speeds due to their lack of experience. Elderly drivers, on the other hand, can feel anxious if their reaction speed, hearing, and eyesight have deteriorated over the years.

The onset of mental conditions such as dementia, Parkinson’s disease, and Alzheimer’s disease can also lead to reduced cognition and confusion.

There are also other possible reasons for “driving anxiety”. For example, the driver may have recently been involved in a road collision or accident. That, or they are just a generally anxious person.


In certain cases, the driver may be transporting a fragile piece of cargo or heavy equipment. For example, the slow-moving van driver in front of you could be carrying a grandfather clock or a window pane. They could be worried about hitting bumps or pot holes at high speed. They may also be mindful of the possibility of heavy cargo moving around.

Some people are also transporting their pets or have a baby on board.

They may be daydreaming

Highway hypnosis is common, and lone motorists can easily slip into a daydream. Sometimes, it is difficult to stay mindful when you are driving by yourself.

In this particular scenario, they might not be aware of the fact that they are driving under the speed limit. They could be thinking about their stressful day, or they could have simply “zoned out” while listening to the radio.


If the motorist is carrying a passenger, they may be deep in conversation. In some cases, the conversation could be heated. For example, an argument between a couple.

Many slow drivers are checking their phones

A lot of motorists will instinctively slow down if they are talking on the phone or attempting to check a text message. This practice is commonplace, despite the fact that using a phone while driving is illegal in many countries.

If this is the case, then you have every right to be annoyed.
Not only are they putting other motorists at risk, but they’re also holding you up with their slow driving.

However, for your own safety, you should maintain a safe distance and avoid tailgating.

Engine limitations

Smaller and older cars can be slow and sluggish. They are slower to take off and can struggle at higher speeds.

For example, a friend of mine was telling me about a work van that he had to transport from one garage to the next. The van was so old that it struggled to reach the speed limit. To make matters worse, if traffic slowed or came to a stop, the vehicle would take a while to recover its speed.

Saving money on gas

Ardent savers know that they will burn less fuel by driving at a certain speed. In many cases, the “sweet spot” for efficiency falls below the posted speed limit.

For example, many transport companies will add speed limiters to their trucks because they know that higher speeds lead to higher fuel costs.

Driving a few miles per hour under the speed limit can lead to significant savings over the course of a year.

Adverse weather conditions

Most drivers slow down when they encounter adverse weather conditions. Furthermore, different motorists will have different opinions about what constitutes an adverse weather condition.

For example, if you drive in Ireland or Seattle, then you will be used to rain and wet road conditions. However, a visitor from a drier climate may not be.

High wind speeds will also affect vehicles differently, depending on their size and shape. Although you might not feel the crosswinds as much, the motorist in the small car in front of you may feel as though they’re about to be launched into orbit.

Sunday drivers

Sunday drivers are motorists who aren’t going anywhere in a hurry. They’re either calm by nature or they’re not too worried about arriving on time. These kinds of people are often quick to point out that everyone else needs to “calm down” and “stop rushing.”

Poor visibility

One evening, my window washer fluid ran out while I was on a highway. It was getting dark, and my visibility wasn’t as great as it should have been. Although I didn’t drive under the speed limit, it was a struggle to keep up with the flow of traffic. It’s easy to imagine other drivers coming across similar issues, especially if dirt and grim have built up on their windshield.

Bad eyesight

Unfortunately, there are a sizeable number of people who will drive without their glasses. There are also a sizeable number of people who should have glasses but don’t. This issue becomes worse at night when visibility is low.

Often, you will see these motorists driving 20 or 30 under the speed limit, frantically turning on their high beams as they struggle to navigate some of the darker roads.

People drive slower in unfamiliar surroundings

People have a tendency to slow down when they are driving in uncharted territory. This is because they are unsure about what lies ahead. This is particularly true for smaller, winding roads. The situation is made worse when the motorist in question is actively looking for a place or a specific turn-off.

This article was posted in Cars on October 24, 2014.