Team Sterling, led by Jane McEvoy, stumbled to a second consecutive defeat on the BBC One reality show and were given a major dressing down by Lord Alan Sugar in the boardroom.
McEvoy, O'Connor and Jenna Whittingham ended up in the final showdown with Sugar, but the 20-year-old restaurateur got the axe after it was revealed that she fell asleep in the back of a car during the challenge.
O'Connor blamed McEvoy for a lack of clear leadership and for changing the final product, but she hit back: "It was a thought out discussion and you were asleep!"
In his final summary, Sugar sniped at all three candidates, commenting: "All three of you have got your own businesses and all three of you have made fatal errors here and I'm sitting here thinking which one of you has got the ability to run a business in which I'm going to invest.
"You should have all known better."
Speaking after her firing, O'Connor said: "I was there to achieve a business investment, I didn't get it. I'll get it from someone else or I'll make my own money and do it myself."
Earlier in the task, the boys' team had also been divided over their eco-bin product, but ultimately proved triumphant with 13,000 sales. They were rewarded by Lord Sugar with a meal at The Ivy.
The Apprentice continues next Wednesday at 9pm on BBC One.
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