You need to realize that state agencies, with few exceptions, cannot adjust staffing on the fly like a private company. That said, maybe a quarter of the complaints filed in CA are dismissed fairly quickly as there was no violation or a negligible violation. The licensee will never even know a complaint was filed. About the same number are closed with an educational call to the appraiser when there was a violation but it did not significantly impact credibility. The rest will get a letter from the state requesting their workfile. As to how long it takes from there is a workload issue. The ASC requires complaint resolution by the state within 12 months unless there are documented circumstances. Again, the state has limited flexibility on staffing, and it takes 6-12 months to transform a new hire appraiser into an investigator. (CA is a bureau, not a board, and uses credential-holding staff investigators.) These stats are consistent with what I was telling the public before I separated from the state. They may or may not be valid today.
As for fishing expeditions, the goal of the investigation is to determine if there were violation of law, not issue citations (or higher). Fishing expeditions would be foolish, be a waste of limited resources, and serve no purpose ... but I understand why licensees need to think this.