What is the test for ineffective assistance of counsel?

"To establish ineffective assistance of counsel, [defendant] must show that [his] counsel's performance was deficient and that [he] suffered prejudice from the deficient performance. [Citation.] On direct appeal, if the record '"sheds no light on why counsel acted or failed to act in the manner challenged,"' we must reject the claim '"unless counsel was asked for an explanation and failed to provide one, or unless there simply could be no satisfactory explanation."' [Citation.]" (People v. Caro (2019) 7 Cal.5th 463, 488.)

Page 15