What is the test for ineffective assistance in a personal injury case?

"If the record contains no explanation for the challenged behavior, an appellate court will reject the claim of ineffective assistance 'unless counsel was asked for an explanation and failed to provide one, or unless there simply could be no satisfactory explanation.' " (People v. Kipp, supra, 18 Cal.4th at p. 367, 75 Cal.Rptr.2d 716, 956 P.2d 1169; citation omitted.)