Is a defendant's failure to appear at a hearing not willful but intentional?

Defendant contends his failure to appear was not willful because "he [did not] intentionally fail to appear. [Citation.] He merely overslept." The trial court was in the best position to determine the credibility of the claim that defendant failed to appear because he overslept (perhaps as a result of taking care of his terminally ill father and elderly mother). (See People v. Coffman and Marlow (2004) 34 Cal.4th 1, 78 [because the trial court can observe the demeanor of a witness, it is in the best position to assess credibility].) However, the trial court did not explicitly make that determination, nor does it appear that the trial court implicitly made the determination.