Cristina Yang in Grey's Anatomy is unabashedly ambitious and one of the most intelligent Shondaland leading ladies. She is unapologetic about who she is and relentlessly pursues her one objective in life--to become the best cardiothoracic surgeon that she could.

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But while Yang did several things on the show that she could be proud of, saving lives and being a good friend, she also did several other things that lacked empathy or came across as incredibly self-centered. A deeply layered personality, Cristina both frustrated fans and made them proud.

The Most Shameless Things Cristina Did

Taking Advantage Of Burke's Tremor

Cristina and Burke standing on a balcony in Grey's Anatomy

Cristina Yang believed in cut-throat competition. And unfortunately, the entire episode involving the tremor in Burke's hand showed that while she was capable of being loyal, she was also equally capable of exploiting a complex, morally grey situation to her advantage.

Some fans wonder is Cristina didn't really use the situation so that she could have more practice in performing complex surgeries that were way beyond her years and expertise. While being loyal to Burke and keeping his secret was what ostensibly drove her, she did gain a tremendous lot from the charade herself. If that was really an ulterior motive behind her holding her tongue, then that was pretty disturbing and certainly quite shameless.

Telling Teddy That She Could Have Owen

Teddy performs surgery with Cristina in Grey's Anatomy

This is a slightly controversial point since many fans adore Cristina for being strong enough to go the extra mile to pursue her passion. But the fact is that Cristina was once ready to give up Owen in exchange for Teddy staying back and mentoring her at Seattle Grace.

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The moment in season 6, "Blink", when she tells Teddy that she could have Owen if that would convince her to stay on is one of the most intense in the Yang-Altman relationship. Cristina has been generous in her profusion about how she needs Teddy to stay at the hospital when Teddy tells her that she wants Owen. In that moment, and probably without realizing the full implication of what she was saying, Yang says that Teddy could take Owen if she wanted. Of course, she is herself stunned after the realization dawns on her but somehow the willingness to give up the man she claimed to love in direct return for a mentor who made her a better surgeon seemed to push the moral boundaries a tad bit.

Favoring Shane

Shane and Crsitina smiling Grey's Anatomy

Entangling with Shane Ross was one of the most shocking things Cristina did on Grey's Anatomy. She developed a peculiarly toxic relationship with the young intern who dared to behave in an insubordinate manner with his other superiors simply to please Yang, and the latter never put him in his place.

Not only that, she also got into a sexual relationship with him that seemed to indicate that she had suddenly lost her way after her breaking up with Owen and losing the Harper Avery. The way she indulged Shane, let him flatter her ego, and allowed him to be way out of line was deeply frustrating for fans.

Her Terrible Bedside Manners

Cristina Yang in resident's uniform Grey's Anatomy

Cristina's terrible bedside manners didn't stand her in very good stead with patients, especially with those who looked for a bit of reassurance from their doctors.

She never believed in sugar coating, something that made her come across as cold and even unsympathetic as a doctor. In spite of being an extraordinary surgeon in the making, she needed to learn how to be more compassionate and understanding, especially in the first few seasons,. Yet, from being rude to her patients to scouring for the coolest surgeries, and even telling Izzie as she sat taking her chemo therapy that cancer patients had a lot of fun because they got delicious ice creams, Yang was reprehensible at times.

The Feud With Meredith

Meredith and Cristina talking in the hospital lobby in Grey's Anatomy

Cristina's needless feud with Meredith for the better part of season 10 was one of the times when fans felt bewildered and even hated Yang at times.

From judging Meredith for devoting less time to surgery after having her son, to telling her that she wasn't as good a surgeon as Cristina herself as her priorities had changed, Cristina behaved quite atrociously in this season which was also her last in Grey's Anatomy. The conflict reached its peak when Cristina used Meredith's 3D printer knowing very well that it would ruin the latter's research. Suffice to say, this was utterly shameless of her.

The Most Selfless Things Cristina Did

Doing Her Best For Izzie

Izzie, Alex and Cristina laughing at George's funeral Grey's Anatomy

Cristina could be annoying at times on Grey's Anatomy but she was the sweetest when Izzie informed about her cancer diagnosis. As the only one among the original group of interns who was capable of staying emotionally detached from her patients, Izzie hoped that Yang would be able to stay neutral and approach her illness as a doctor and not as a friend.

Yang indeed did her best for Izzie, doing a ton of research, setting up appointments for her with the best oncologists and pushing Izzie to get treatment. It was also her who eventually informed Miranda and Alex about Izzie's condition which of course finally led her to getting her surgery and gradually beating the cancer.

Being There For Meredith

Cristina Yang (Sandra Oh) and Meredith Grey (Ellen Pompeo) in "Grey's Anatomy."

For all their fight, Cristina had always been there for Meredith. Ever since the pilot their friendship cemented over the years as Cristina stayed like a pillar with her 'person' through all the many ups and downs in Meredith's life, and fans know she had been through more than a few terrible challenges.

Of course, several of those challenges Cristina had herself faced, such as the horrifying plane crash or the hospital shooting incident. But when it came to supporting Meredith through the difficulties she went through, such as almost drowning to death, boyfriend and later husband troubles, and simply being there for her in every little thing, keeping her secrets as a best friend should, Cristina could always be relied on.

Not Letting Anyone Change Her

Owen and Crsitina look at each other Grey's Anatomy

Cristina Yang never let anyone change her as a person and that was one of the best things she did that she would be very proud of. An inspiration for many, she always stood up for herself in her relationships and never compromised with her single minded dedication towards surgery.

Cristina almost did let her feelings for Burke take over who she was and became ready to walk down the aisle with him. But even in this relationship she held her own when it came to her decision not to have children. The same issue became a point of contention in her marriage with Owen who wanted kids and a family. But here too she didn't compromise or go along with what Owen wanted simply for his sake. While she did love him very much, she didn't let that come in the way of her dreams.

Taking Care Of The Others Post-Crash

Crsitina, Meredith and Derek in the night after plane crash Grey's Anatomy

Despite her general lack of empathy, Cristina was good at heart and usually ended up doing the right thing, both as a doctor and a person.

RELATED: 10 Cristina Yang Plot Holes In Grey's Anatomy That Make No Sense

After the horrific plane crash of season 8,one of the most shocking finales in Grey's Anatomy, Yang was the only one of the victims who was relatively stable. As the others lay in chaos, some dead, some dying or severely injured and others simply devastated, Cristina tried to keep her head. She continually helped Mark Sloan who was collapsing repeatedly, and tried to keep young Lexie's body safe in the wilderness. She was, after all, human and thus left with severe PTSD afterwards, but for her contribution during the few days after the crash, she could definitely be extremely proud.

Saving Derek Shepherd

Gary Clerk pointing gun at Yang and Avery Grey's Anatomy

One of the things Cristina did that she could take immense pride in was saving Derek Shepherd's life during the hospital shooting, one of the most shocking finales in Grey's Anatomy.

Cristina saved Derek at a time when she wasn't really qualified to perform such a complex surgery. But she gathered the courage and the confidence to go ahead knowing that they had no other alternative. And even at gunpoint, while tears ran down her face profusely and in the midst of utter chaos, she managed to do the unthinkable and save Derek. Of course, the latter died anyway a few seasons later in a tragic road accident, but that didn't take anything away from the feat Yang had performed.

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