What is the legal test for ineffectiveness?

The approach to an ineffectiveness claim is explained in Strickland v. Washington, 466 U.S. 668 (1984), per O'Connor J. The reasons contain a performance component and a prejudice component. For an appeal to succeed, it must be established, first, that counsel's acts or omissions constituted incompetence and second, that a miscarriage of justice resulted.