carelessness       
noun [ U ] uk/ˈkeə.ləs.nəs/ us/ˈker.ləs.nəs/
 不小心|疏忽
the fact of not taking or showing enough care and attention
  Most of the forest fires this spring were caused by human carelessness. 今年春天大部分的森林火灾是由人为疏忽造成的。 
 A moment of carelessness can cost an animal its life. 动物一朝不慎就会丢了性命。 
 See: careless
 - More examples
 - Many cases of frostbite result from inadequate clothing or carelessness and stupidity.
 - Neither negligence nor carelessness played a role in the accident.
 - He was criticized for his arrogance and carelessness.