This tutorial gives you a list of characteristic features that any tester must possess to become a good tester. And these features, in turn, help a lot in determining the Quality Quotient of a Tester.
Why am I talking ONLY about a Tester? And Why not a Developer or any other role?
I just feel that all the work involved in SDLC in delivering a software is quite simple when compared to the responsibility of a Tester.