So, you come up with an idea that seems to be a good solution for an existing problem, or a different approach for solving a problem which makes the existing solutions obsolete or not needed anymore.
Then you devote yourself to googling for relevant documentation, making plans about setting up the project, finding fundings and people to work with and other stuff for days and nights.
Finally when you are about to start -while lazyly surfing on the net- you find out that the idea you built your multi-billion-dollar-dreams on, has already been implemented in zillions of ways on the very same topic. you just missed the relevant links/documentations by not using the correct keywords in searches.
what would you do in this situation? give up everything you've planned? start your business/project anyway? if you chose not giving up, what would be your motive to continue?