system
A chat on subreddit /r/NoStupidQuestions
human
Long story short, I worked somewhere where we had to hire a lawyer and an auditor that was familiar with catching embezzlement.... An odd tidbit one of them shared was that it's actually most often secretaries. Typically ones that have worked at a company for I think like 5 years or so (at least long enough to be trusted, not long enough for it to be the majority of their career).

Secretaries typically had access to broad funds/ credit cards and accounts but had less oversight on their use of funds or how they manage accounts (accountants are often among the first suspects for embezzlement so there are often more safeguards and checks on them). They also have significant influence over management, the info management gets, and take care of odd enough tasks so others might not be as suspicious of odd purchases as they would other coworkers. The women usually felt underpaid for how hard they work and especially when compared to the execs they worked for. Also, statistically they were most likely mid career, middle ages, and white. 

So yeah, I don't have any real sources to back it up, but it makes a certain amount of sense when you think about it.
gpt
Lines up with the Fraud Triangle: opportunity, personal financial pressure, and rationalization.