Introverts/extroverts ratio in teams

Just something that I've noticed during my first watch of Naruto OG and Naruto:Shipuden and after rewatching some scenes on YouTube.

When it comes to genin/chunin teams, usually there were 2 extroverts and 1 introvert with two exceptions:

Naruto (E), Sakura (E) and Sasuke (I)

Ino (E), Choji (E) and Shikamaru (I)

Lee (E), TenTen (E) and Neji (I)

Temari (E), Kankuro (E) and Gaara(I)

Zaku (E), Kin (E) and Dosu (I)

Rin(E), Obito (E) and Kakashi(I)

The two exceptions are Kurenai's team (the only extrovert was Kiba) and Sarutobi's team (all three of the legendary sanin were extroverts).

When it comes to the Akatsuki's duos, every time there was a ratio of 1 extrovert to 1 introvert:

Sasori (I) and Deidara (E)

Hidan (E) and Kakuzu (I)

Itachi (I) and Kisame (E)

Pain/Nagato (E) and Konan (I)

Obito (E) and Zetsu (I)

Taka Team when the joined the Akatsuki (there were two extroverts, Karin and Suigetsu, and two introverts, Jugo and Sasuke).