Use cases are derived from the scenario in the real world. Tester has to think about positive & negative output & write teh test cases depending on it
For ex if the real world scenario is user go to atm & debit some amount Now Use cases are..User enter wrong Pin no user incoorectly enter card user want to debit amout more than in his account usre withdraw such amout because of that the least balance req. is not remain etc
Depending on the CMM level of the company the step at which the tester is involved get decided.
In CMM level 5 4--Starting from the requriment pash ithe tester is involved & he/ she can prepare teh doc related to it Can put points of req that can not be implamented inn real world etc.
In CMM 3 &2 --whae everything is finalised & tester asked to write test cases for that
In CMM 1 & 0---When any one module is completed directly the code is handover to tester & asked for testing..!
