Stay Hard is the signature catchphrase of David Goggins, a former US Navy SEAL and ultramarathon runner who became known for extreme endurance challenges and blunt motivational speaking. The phrase spread through his social media clips, interviews and workout videos, where fans repeated it as shorthand for mental toughness and refusing to quit. It remains popular online because it is short, instantly recognisable and easy to drop into gym, running and self-discipline content, giving creators a quick way to signal grit without needing a longer speech.