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Why do drivers speed?

By Dr Lisa Dorn

Speed is one of the most important crash contributory factors increasing both the severity and frequency of crashes. According to Department for Transport statistics published in November 2023, over a third of fatal collisions in 2021 were speed related. From a Human Factors perspective, speeding reduces the time available to process information, make decisions, and initiate a response to avoid a collision. It has been argued that if speed could be reduced by just 1-3 mph there could be 10%-30% reduction in collision injuries (Molin and Brookhuis, 2007). Speed limits, and enforcement of the speed limits, are the most widespread attempt to make drivers choose safer speeds, along with speeding campaigns, road design and signage but still 50% of road users are reported to break the speed limit every day (Yannis et al, 2013).

So why do drivers speed? What propels drivers to exceed the speed limit? How do motives influence speed choice? Road safety practitioners need to understand why drivers exceed the speed limit as this has important implications for designing effective interventions. Psychologists have investigated the reasons why people habitually speed and identified two basic types of motives: intrinsic and extrinsic motives. 

Intrinsic and Extrinsic Motives

Intrinsic motives explain speeding behaviour that does not have any obvious external rewards. You do it because it’s enjoyable. Speed is intrinsically motivated when performed as an activity for its own sake - the behaviour itself is its own reward.  Here, drivers exceed the speed limit to maximize the pleasure or fun of driving, seeking thrills and spills that the behaviour offers. Other intrinsic motives may be more socially oriented. For example, being seen as a slow driver has the image of someone who lacks self-confidence and driving ability and drivers may be motivated to avoid this characterisation, preferring to be seen as a confident risk-taking driver with exceptional skills when driving at speed.


Extrinsic motives explain speeding behaviour as the goal to achieve some form of external reward or avoidance of punishment. In this case, you engage in behaviour to obtain something of value in return or avoid something unpleasant. For example, your income is dependent upon how many deliveries you make or reaching some target. These outside incentive or pressures can significantly influence speed choice, especially when driving for work.


Developing your knowledge and skills in Human Factors

The first module of Level 2 of the Human Factors and Road Risk Management programme explains what motivates driver behaviour and how motives influence risk. Road safety practitioners will learn new models and theories on the Human Factors for managing road risk. The programme is delivered live over 2 full days by Dr Lisa Dorn and includes approximately 15 hours of learning material including a pre-read workbook. The course encourages active, value-driven discussions and tailored to the specific interests of the delegates attending. The next course runs on 12th and 13th March 2024. For more information, click here


Level 2 is only available to people that have been accredited at Level 1. Book your place by completing the form: -


Key references

Molin, E. J., & Brookhuis, K. A. (2007). Modelling acceptability of the intelligent speed adapter. Transportation research part F: traffic psychology and behaviour10(2), 99-108.


Yannis, G., Louca, G., Vardaki, S., & Kanellaidis, G. (2013). Why do drivers exceed speed limits. European Transport Research Review, 5, 165–177.



PsyDrive is Specialist provider of professional road safety training, research, assessment, and interventions for improved road safety.




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