In Solidity, it's possible to write code that does not produce the intended effects. Currently, the solidity compiler will not return a warning for effect-free code. This can lead to the introduction of "dead" code that does not properly performing an intended action.
For example, it's easy to miss the trailing parentheses in msg.sender.call.value(address(this).balance)("");, which could lead to a function proceeding without transferring funds to msg.sender. Although, this should be avoided by checking the return value of the call.
It's important to carefully ensure that your contract works as intended. Write unit tests to verify correct behaviour of the code.