Question

why friction called a necessary evil

Answer 1

Friction is necessary for any object to move although it keeps on resesting the movement of the object thus it is called a necessary evil

Answer 2

Answer:

Frictional force causes a lot of losses in general upkeep and wear and tear of machinery. Hence it is considered as a evil. But almost all crucial tasks cannot be carried out without the presence of friction. ... Hence it is considered as a necessary evil