What is the goal of the tester person?

As a tester, what is the goal of the tester person? Kingly clarify

Responsibility of the tester is to achieve testing objective which is, to discover the maximum number of defects with a minimum number of resources before the system is delivered to the next stage. A good tester does not rely on few times testing of the program but carries out a thorough analysis of the program to devise test cases that can be used to test the system systematically and effectively from every perspective of testing each and every functionality.