Tsukishima's past, particularly his experiences with his older brother Akiteru, who was once a prominent volleyball player, has a significant impact on his initial reluctance to fully engage in volleyball. Tsukishima feels overshadowed by his brother's achievements and struggles with feelings of inadequacy and insecurity. This leads to Tsukishima adopting a defensive and aloof attitude towards volleyball, as a way to protect himself from potential failure or disappointment. It is only through personal growth and understanding that Tsukishima is able to overcome his past and fully embrace the sport.