The latter, I hope were better than that. And to prohibit the possible offenders here, no need to jail them. Just forbid them from serving in capacity that can cause such harm: bar them from serving in executive or decision making role.
Number 4 obviously doesn't apply in the US justice system, but number 3, deterrence, is imho the major argument for putting executives or employees in prison. The threat of punishment can be a strong motivator, especially in corporate settings. But it only works if punishments are actually delivered after someone crosses the line
Which would seem to suggest that stuffing even more people into prisons may not help much; what we really need is to dial back some of the gutting of regulatory bodies that's made it so easy for corrupt behavior to flourish in the first place. Sunlight continues to be the best disinfectant.
And you can kind of see it on an international scale? The "better regulation" approach is favored by places like EU countries, while the "throw the leaders in jail" approach is more favored by places like Russia and China that don't exactly seem to be ideal role models for how to keep corporate corruption in check.