I think you are confused.
iCloud was NOT hacked. There was simply a mistake made by a customer service rep as acknowledged by Apple.
Except that Wired claims to have replicated the "mistake" at least twice (on top of the original attack). So that's a systematic error, and dedicated self-attack team ("tiger team") could have found that, and the hole could have been closed.
If you run a system on the scale of iCloud, and you don't crack it yourself, you can bet someone else will save you the trouble.