In Formula One, a position can change without a conventional on-track pass. Stopping at different moments allows teams to exploit differences between fresh and used tyres. The undercut and overcut both depend on the circuit, traffic and tyre behaviour; neither is a universally effective formula. Their value comes from the particular sequence of laps surrounding the stops.
The undercut
A following driver stops first and attempts to use fresh tyres to complete faster laps before the rival makes a stop. Success depends on more than the stationary service time. The new tyres may need warming, and traffic after the pit exit can remove the advantage. Clear track can therefore be central to the decision.
The overcut
The leading driver may stay out longer, hoping that clear air or still-effective older tyres creates enough time to retain the position after stopping. That approach becomes vulnerable if the tyres deteriorate rapidly. Compare consecutive laps before and after both stops rather than selecting one unusually quick lap as proof that the strategy worked.
When circumstances change
A safety car, virtual safety car or change in weather can alter pit-stop losses and the appropriate tyre choice. A sound plan may become ineffective because of an event that was not known when the decision was made. A fair assessment separates the information available at the time from what happened afterwards.
