When writing code, it is important to ensure that each statement serves a purpose and contributes to the overall functionality of the program. When
they have no side effects or do not change the control flow, they can either indicate a programming error or be redundant:
  -  The code does not behave as intended: The statements are expected to have an effect but they do not. This can be caused by mistyping,
  copy-and-paste errors, etc. 
-  The statements are residual after a refactoring. 
Exceptions
The rule does not raise an issue on statements containing only a semicolon (;).