When they were together with the Los Angeles Lakers, Kobe Bryant and Shaquille O’Neal formed arguably the greatest one-two punch in the history of the NBA. Once they split up however, Bryant took a lot of criticism.
O’Neal was the clear first option for the majority of their time as teammates. Furthermore, he was also Finals MVP for all three of their championships together. When he left and won a championship with the Miami Heat just two seasons after leaving the Lakers, many came to the conclusion that he was main reason for the Lakers success.
Related to that was the assumption that Kobe could not win an NBA title without Shaq by his side.