Technically there are plenty of crimes where it is not only reasonable but morally obligatory to be lenient to a first-time offender. Like copyright infringemen

Technically there are plenty of crimes where it is not only reasonable but morally obligatory to be lenient to a first-time offender. Like copyright infringement or sodomy. But in those cases it's also obligatory to be lenient to a second-/third-/etc-time offender, because the law criminalizing them is unjust. Similarly, I strongly suspect that the law unjustly fails to criminalize Slack's negligent disregard for their users security in this case. I agree that, crime or not, it was intentionally committed, and does not warrant lenience, though.