Originally Posted by
Often1
If you no show for your ticketed flight and take no other action, your ticket may be cancelled and will retain whatever value it retains under its fare rules. That might be $0. It is possible that you can get your ticket reinstated at the airport, but not guaranteed and it will mean standing around while that happens.
Again a roulette issue which comes back to your risk tolerance.
No need to worry about ticket no value. I've stand by for later same day AA flight over the years. No issues with ticket having no value due to "no-show" the original flight. Airport agent will have to find your PNR but will just work with that PNR in getting you on the standby list.
But you do raise a valid point that one should call AA to confirm whether no-showing the original flight will cause any subsequent flight (eg return) to cancel out immediately after original flight is closed. All my later same day standbys have always been one-segment bookings so no experience with doing this when there are additional flights are in the future.