(idiomatic) To have endured all that one can. / (idiomatic) To be broken or worn out beyond repair. / (idiomatic) To be dead or close to death.

misconstruction of have had it

simple past tense of have had it

Alternative form of iotacism

(UK, mildly vulgar) expression of annoyance.

(UK) expression of surprise, contempt, outrage, disgust, boredom, frustration.

For success, and especially to obtain employment, one's knowledge and skills are less useful and less important than one's network of personal contacts.

(idiomatic) That is it; that is the situation or state of things. / (idiomatic) Used to introduce a speaker's interpretation of what has just transpired or been described

(mildly vulgar) An expression of surprise, outrage, or frustration.

It is better to do something oneself than to rely on others to do it well.