@Darwin. Test cases should be written during the earlier stage of the software development life cycle. Gathering software requirement is the best phase to write the test case. Testers should have to follow these points for effective test cases which can also increase the efficiency of those test cases:
– Detailed requirements specified by the Customer
– Keep a track of all used cases
– Requirements based on functionality in detail
– Project Plan of Application to be created
– Brief documentation of the project milestones
To read more about how to create test cases proficiently, this blog helps a lot in clearly digging the things deeper: https://www.bugraptors.com/improve-test-case-efficiency/
[reviewed by mod, link ok /JO]