How many inventions would have ceased if innovators were scared of failure? From light bulbs to AC current to airplanes. We have history to say it all.
The same goes for entrepreneurship. The risk appetite and going against all odds defines success. The path is filled with failures, rejection and pain. But that is the joy of building something.
Most companies or research fail when top heads give up.
There is no such thing as failure. It is only experience that makes us better at sailing on the life journey.