Even if someone makes 300+ reports, do all the reports stay in the history, starting from the first report, or are only the reports mentioned in the history starting from the 301st?
To see your report history, you need to have at least 300
good reports, not 300 reports.
Do these reports have a visibility decay time, or are the details of every report made visible, even after years?
Your report histroy (if available) displays your reports in the past 30 days.