What is the test for determining whether a defendant has made a mistake in assembling all their evidence at trial?

'Whether the case involves intrinsic or extrinsic fraud or mistake is not determined abstractly. 'It is necessary to examine the facts in the light of the policy that a party who failed to assemble all his evidence at the trial should not be privileged to relitigate a case, as well as the policy permitting a party to seek relief from a judgment entered in a proceeding in which he was deprived of a fair opportunity fully to present his case.'' (Kulchar v. Kulchar, 1 Cal.3d 467, at 473, 82 Cal.Rptr. 489, at 492, 462 P.2d 17, at 21, quoting from Jorgensen v. Jorgensen, 32 Cal.2d 13, 193 P.2d 728.)