It's also to (at least theoretically, can't comment on Dodd-Frank specifically but other areas of compliance that I've dealt with) ensure that even good actors

It's also to (at least theoretically, can't comment on Dodd-Frank specifically but other areas of compliance that I've dealt with) ensure that even good actors don't stray too far. "Normalization of deviance" is a real issue, even for well-intended individuals and organizations. Having some manner to hold people to account can reduce (though certainly not eliminate) those incidences as well, or provide a way to get back on track (including, potentially, paths for self-reporting and rectifying to discourage coverups).