Does the discretionary exclusion rule extend from origin to completion of any governmental activity?

Certainly it allows a greater predictability of decision. [249 Cal.App.2d 291] Even the early cases, stating that the discretionary exclusion rule extends from origin through completion of any governmental activity, did not apply the rule literally. They recognize that every act performed by a human being involves the exercise of Some discretion. Ne Casek v. City of Los Angeles, supra, 233 Cal.App.2d 131, 43 Cal.Rptr. 294, refers to this. On page 135, 43 Cal.Rptr. on page 297, the court says, quoting from Ham v. County of Los Angeles, 46 Cal.App. 148, 162, 189 P. 462: "(I)t would be difficult to conceive of any official act, no matter how directly ministerial, that did not admit of some discretion in the manner of its performance, even if it involved only the driving of a nail." (He who says discretion is not involved in driving a nail has either never driven one or has had a very sore thumb, a split board, or a bent nail as the price of attempting to do so.)