when to do manual testing

1Literally, it means testing an application with your hands. 
2It is performed by humans, no tools or codes are used.

1-Unstable test cases
2-Tests that you will only run only once.
3-The only exception to this rule is that
4if you want to execute a test with a very large 
5set of data, even if it’s only once,
6then it makes sense to automate it.
7-Unfinished functionality
8-Visual test cases
9-Also Tests that need to be run ASAP
10which usually a new feature which is
11developed requires a quick feedback
12so testing it manually at first making sense.