Conditions decide whether a print updates the official high, low, last price and consolidated volume. Plenty of prints do none of these, which is why raw tape data must be filtered before it is charted or backtested.
Ignoring them produces phantom candles. A late-reported block at a stale price can draw a wick to a level where nothing actually traded at that moment.
Example: a stock trading 60.00 shows a 60,000-share print at 58.20 flagged as a sold-last late report from nine minutes earlier. Included naively, the chart prints a 3% spike low that never existed; filtered correctly, the day's low stays 59.86.
Related: tape-print, consolidated-tape, benchmark-close, time-and-sales