The practice guides treat each motion as a discrete thing – but they are not as the case law clearly indicates. The appropriate motion is determined by the facts of the case… or by the equities; or by the jurisdiction conferred by statute; or the court’s inherent discretion.
For example, a party requesting that the court reconsider a ruling has the option of a motion for reconsideration, a 473 motion, or a writ of review or mandate. The court has discretion to “construe” a motion for reconsideration as a request to renew the original motion, or as an analogous motion for a new trial or a motion to vacate… A complaint for declaratory relief and petition for a writ of mandate may be combined in a single action.
The court in Passavanti v. Williams (1990) 225 Cal.App.3d 1602 suggested that assuming the trial court has the authority to consider a motion regardless of its label, for the benefit of the opposing party and for purposes of appellate review, the court should clearly indicate its intention to do so and to clearly identify the motion it is considering.