How was living in a tenement dangerous

Tenement are urban dwellings occupied by impoverished families. They  are  dangerous apartment houses because they barely meet or fail to meet the minimum standards of safety, sanitation, and comfort. As a result people living there are prone to safety hazards and infections diseases. Lack of comfort also ensures that they do not achieve their fullest potential.

Sasuke was obssed by naruto being powerful so he wants to be more powerful. and at killed hi own brother and became rouge ninja