This paper attempts three things. The first is a defense and the rest is a critical appraisal of a crucial notion involved in the defense. First, it argues that John Turri’s criticisms of Ernest Sosa’s virtue epistemological account of knowledge that it fails to rule out Gettier cases rest on a misconstrual of the “because of clause” which Sosa employs. Turri overlooks the notion of “success manifests competence” which is central to understand the “because of” clause. Thus, the position of (...) Sosa is defended from the criticisms of Turri. Secondly, it critically examines the notion of “success manifests competence” which is a crucial notion in Sosa’s account. It argues, unlike what Sosa seems to hold, some of the conditions which Sosa provides for “success manifests competence” are not necessary. It also clarifies, by agreeing with Sosa, that the conditions he provides are not sufficient for “success manifests competence.” Thirdly, it briefly argues that Sosa’s occasional insistence that complete competence should be present in the case of success manifests competence brings in certain internal tension in the account of Sosa. Thus, the paper defends Sosa’s position from the criticisms of Turri; but it also clarifies Sosa’s account as well as raises some criticisms to it. (shrink)