The lag is the thing nobody accounts for
Public records are not a feed. Every system in this playbook publishes on its own cycle, and the gap between an event and its record is frequently longer than the window in which the research would have been useful.
A deed is recorded within days of closing in some counties and weeks in others, and the assessor's roll then updates on an annual or semi-annual cycle behind that. A business registry reflects a change when somebody files it, which may be at the next annual report rather than at the transaction. Probate opens weeks after a death and runs for a year or more. The practical consequence is that checking once and finding nothing is not a result. Knowing the expected lag for the record you are checking is what turns a null finding into information rather than a dead end.