Comment 12 for bug 1232814

#10 I can't understand how this isn't intentional, it was purposely removed before 12.04 was released, but there was a workaround to get it back in the menu, now oddly the ability to use that workaround has also been removed. Windows 8 also by default removes the hibernate option, but it is simple to add back.

As Sergio says, suspend is also problematic, I have lost count of the amount of times I have opened my bag to find my laptop has awakened from suspend in my bag and toasted away, not to mention the times when it flatly refuses to suspend at all and just resumes before I get out of my seat. Forcing me to either close down every application, make sure everything is saved and then shutdown, or hibernate. Then there is also the all too frequent problems of Compiz hanging or crashing when resuming from suspend, forcing a hard reset. Not to mention the problem Sergio points out of the device inexplicably losing power whilst in suspend mode.

I've always found suspend a far riskier option than hibernate.