But failure is always an option.
It's the most likely option. It's far more likely than success. It's much easier too. If it wasn't, a dramatic pep talk would be unnecessary.
So what is our leader really saying by telling his subordinates that "Failure is not an option"? He's probably saying, "Listen to me guys. You better not screw this up!" That's far from inspirational.
Failure is critical to success; almost always a precursor to it. The key is managing it, such that the costs are small but the benefits are potentially huge. That's real leadership.