Below are some scenarios when Manual Testing is preferred over Automation testing:
1. When the application under test is very small, you do not need to go for Automation Testing.
2. When the application is very complicated and has too many modules, Manual Testing is the only solution.
3. Look & feel and UI alignment related testing always requires Manual Testing.
Thus, we can say that manual testing cannot be ruled out altogether, although its scope is less as compared to Automation Testing.