Going to Mars takes about the same delta-v as the moon.

SpaceX launches 80% of the world's mass to orbit, they probably know what they're doing.

Starship is an extremely hard problem, and their aim is to reduce cost of getting mass to orbit by another 10x after Falcon 9 did the same.

Falcon 9 needs about 4% of fuel to land on a ship, 14% to return to launchpad

Why would you say they've had 100% failure rate? What did you think the reason was to launch and how did it fail?