This paper focuses on damage processes other than the main one observed and studied in pavement design. Previous research has targeted the experimental fatigue performance of tack coats. The French Pavement Design method has been chosen herein to illustrate how interface fatigue performance can lead to improved design, especially when pavements are subjected to repeated horizontal loadings. In a curved pavement section, longitudinal top-down cracking is observed, and this damage process may also be taken into account during the design approach. A 3D finite element model has been derived to assess pavement lifetime. In conclusion, it is proposed to include the fatigue performance of interfaces when designing pavements with horizontal loadings and thin surface layers.