What does it mean?
The phrase means that Fortuna, the Goddess of luck, is more likely to help people who bravely go after what they want. These people will most likely be more successful than people who try to live safely.
Where does it come from?
Its earliest recorded use is in latin as ‘Audaces fortuna iuvat’ by the second century BC playwright Terence, Phormio.
The Roman dictator and consul Lucius Cornelius Sulla was said to believe in the influence of the goddess Fortuna in his life. He was a consummate risk-taker, achieving martial distinction by taking risks on the battlefield such as wearing disguises and living among the enemy. He was also the first of the great Republican Romans to march upon Rome — a great taboo, but one which cemented his power and influence. Sulla so believed in his favor with Fortuna that he took the agnomen Felix which means “lucky” and gave his twin son and daughter the antiquated praenomina Faustus and Fausta because those names were also associated with luck.
Julius Caesar also transformed his fortunes when he marched on Rome, declaring alea jacta est (the die is cast) as he crossed the Rubicon river. The utterance was a commitment of his fate to Fortune. While Caesar was a professional soldier, many of his victories were achieved by taking bold risks which exposed him and his troops to significant danger, but resulted in memorable victories.