I want to drop off my luggage at the connecting city for final destination which is my home. My luggage is already tagged for final destination at my original destination. All i have to do is drop off the luggage at the drop off site outside of customs. Someone will pick the luggage for me at the final destination. Do I need to check in and let airline know or not bother checking in and let my luggage go to final destination since it is already tagged for final destination. Will the airline pull my luggage out if they find out I did not check in? or will they know? Connecting time is about 3 hours. I do not need a refund And this is the last stop.
Airlines only transport luggage without the owner being on board if it was the airline's fault that it was not transported on the correct flight earlier. In your scenario, they will unload your baggage before departing from your port-of-entry airport if you do not show up for the connecting flight.
As Moo wrote in a comment to this answer, this is a security issue, and airlines are very strict about it for that very reason - you do not want any unattended baggage onboard an aircraft when the "unattended-ness" could be deliberate on part of the passenger.
On a related note: you cannot check in your luggage if the check-in procedure for yourself has not been completed. The only thing that you can do is to get checked in and then not show up at the gate....which gets your luggage unloaded and the flight will be delayed.
It is not possible. Airlines keep track of who is checked in and make calls to that person until the time the gate closes. If someone does not show up, they will remove the luggage from the aircraft. This is to prevent security issues with luggage intentionally sent on a plane without the owner. It is the same reason airlines often asked if you packed your own bags.
Most times, when you check-in for a multi-segment flight, you are automatically checked in for every segment. There is no way to un-check-in.
In some rare cases, you may be checked-in partially. This has happened to me a handful of times, the last one earlier this year when I had an international segment going into Brazil followed by a domestic segment, both on the same airline. In this case, they only checked-me in to international flight even though the luggage was tagged to its final destination and transferred without my intervention. Even in this case, they would have removed the luggage from the flight had I not boarded the domestic flight, regardless if I had checked in for it or not.
Once you check-in, you are checked in for all flights. You would not check-in for subsequent flights unless told to do so because of some operational issue.
If you do not board subsequent flights, you luggage should be offloaded.
If your luggage does make it to the last destination without you, there is a distinct possibility it will be kept at the baggage office requiring you to present identification to retrieve it.