Last year a company was testing their software in a dev/test environment and accidentally sent out an "Integration email" to their customers.  They blamed this on an intern, though a little jokingly, and plenty of people shared their own stories about making mistakes.

I did this once, and only once. I was doing some software testing on a copy of the production database and accidentally sent out thousands of emails to customers. I hadn't scrubbed the email addresses in the copy, but since I also hadn't scrubbed the data, customers got an "extra" email for their account and few complained. My boss, however, complained quite a bit and with good reason.

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