Do root canals make your teeth come out ?

I had my first r/c about ten years ago . Six months later while flossing it flew across the room.
Had my second r/c about four months ago. While flossing it, too flew off.
Do you think root canal “therapy” makes teeth come out thus sending the patient back to the dentist so he can make a new tooth for another thousand dollars? Or do you have luck with them?