What is the burden of proving deficient performance in a motion?

To carry this burden, " ' "a defendant must first show counsel's performance was 'deficient' because his 'representation fell below an objective standard of reasonableness . . . under prevailing professional norms.' [Citations.]" ' " (Lucas, supra, 12 Cal.4th at p. 436; see also People v. King (2010) 183 Cal.App.4th 1281, 1298.) " ' "Second, [the defendant] must also show prejudice flowing from counsel's performance or lack thereof. [Citation.] Prejudice is shown when there is a 'reasonable probability that, but for counsel's unprofessional errors, the result of the proceeding would have been different. A reasonable probability is a probability sufficient to undermine confidence in the outcome.' " ' [Citation.]" (Lucas, at p. 436.)