He's explained it extremely badly, but there is an issue in matches where there is no DRS - such as county matches.
For the easiest example to record, LBWs in matches that don't have reviews don't have replays at all - sometimes you don't even see the umpire declining the decision. Equally, if you don't review an LBW decision when prompted in matches that have DRS, you'll also not see a replay.
First one is an actual dismissal, and the other two are given not out - apart from where I've cut out the balls between these, it's in full with no button press.
I know I've come across third umpire decisions without replays while online - though occasionally that's because for whatever reason the replay is
after the decision.