Is a plaintiff unable to discover a cause of action?

However, a plaintiff's inability to discover a cause of action may occur "when it is particularly difficult for the plaintiff to observe or understand the breach of duty, or when the injury itself (or its cause) is hidden or beyond what the ordinary person could be expected to understand." (Shively v. Bozanich (2003) 31 Cal.4th 1230, 1248, italics added.) Where a professional, such as a doctor or lawyer, commits malpractice, "delayed accrual is justified on the basis that the expertise expected of professionals is beyond the ability of laypersons to evaluate, and on the further basis that it may be impossible for a layperson to even observe the professional's application of his expertise." (Ibid.)