tend to become
大都会に住んでいる人は運動不足になりがちだ。
People who live in big cities tend not to get enough exercise.
共同責任は無責任になりがちだ。
Collective responsibility often means no one takes responsibility.
病人は悲観的になりがちだ。
Sick people tend to become pessimistic.
お前さ、早口になりがちだぞ。
You tend to talk too fast.