On a 500-tick chart, every bar closes after 500 trades print, whatever their size and however long that takes. Active periods produce many bars, quiet periods produce few.
Day traders in futures like tick charts because bar production naturally speeds up when participation rises, which is usually when moves happen. A 1-minute chart, by contrast, spends the lunch hour printing meaningless doji.
Two caveats. First, a tick counts a transaction, not a share or contract, so one 500-lot and one 1-lot count the same; volume-bars fix that. Second, tick counts differ between data providers because of how they aggregate, so a setup tuned on one feed may not reproduce on another.
Related: volume-bars, range-bars, timeframe, time-and-sales