Is plaintiff's evidence insufficient in a personal injury case?

"[W]e simply cannot identify the respects in which the trial court found plaintiff's evidence to be insufficient." (McLaughlin v. City etc. of San Francisco (1968) 264 Cal.App.2d 310, 316.) We are left to speculate as to the trial court's reasons, which is precisely the concern section 657 sought to ameliorate. (Id. at p. 317 ["the 1965 amendment of section 657 was designed to put an end to speculation of this nature, and we are not permitted to infer the trial court's reasons where we have not been told what they are"].)