Valve officially talks about the Steam Winter Sale account fiasco.

[O-D-C]

vivster said:

I work in IT and things like this happen all the time. You won't see it often because usually there are a lot of safeguards in place but it happens and is especially easy to happen in rushed scenarios like this.

The fault is still on them though and an honest mistake does not safe you from responsibility.

I still laugh at anybody who believes this could've been prevented with more money.

QFT, I work at a software solutions company and ya this sorta happens a lot. Not just to us (thankfully) but any tech company. Some issues are just a bit more public than others.