Reference

Shunsuke Nakamura decided to move from Yokohama F. Marinos to Júbilo Iwata primarily due to his dissatisfaction with the influence of City Football Group, stakeholders in Yokohama F. Marinos. Nakamura was reportedly unhappy with the interference in both player and staff personnel decisions by the stakeholders, which contributed to his decision to leave the club he had a longstanding association with.

Additionally, Nakamura mentioned in a statement that he wanted to embrace a new challenge by joining Júbilo Iwata and was willing to contribute everything he had to the new team.

For more detailed information, you can refer to these sources:

• Reddit
• Wikipedia
• J.League News
• Scottish Sun

Here is an image of Shunsuke Nakamura: