When Grey's Anatomy first began, fans were introduced to five optimistic interns who were fresh out of medical school. They were all desperate to become the next prestigious surgeon, like Ellis Grey or Margaret Goodwin. However, only two of them managed to make it to the big leagues.

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One thing fans have learned through the show is that if the Chief doesn't think you're good enough or if you fail your exams, you don't make the cut. You can be kicked out of the program or fired. Viewers got to witness this first-hand as several surgeons have been fired for their incompetence — and rightfully so. Want some examples? Here are five doctors we'd hate to have on-call and five who we'd be relieved to see.

Worst: Izzie Stevens

An image of a smiling Izzie Stevens in Grey's Anatomy.

Although Izzie is one of the kindest and most compassionate people you will ever meet, she was a very reckless doctor. Everyone knows that Izzie was emotionally invested in her patients, but this was also detrimental to her career as she struggled to separate her personal life from the professional.

She forced her fiancé onto the transplant list by cutting his LVAD, nearly killing him. She also incorrectly gave a patient the wrong dosage of medicine, meaning they couldn't get a liver transplant. Izzie was so incompetent and not good under pressure.

Best: Miranda Bailey

Bailey in Grey's Anatomy

One person on the show fans would literally trust with their life is Bailey. She is organized, direct, and has no time for nonsense, which is one of the reasons why she is highly respected by her colleagues. Bailey is also known to have an excellent bedside manner, which has helped put patients at ease.

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So why is she one of the best people to have on call? For one, Bailey has given everything to this job. Her first marriage fell through because she put the job first. The Hippocratic oath is everything to her, which is why she's a great person to have on call.

Worst: Leah Murphy

Another surgeon you would have dreaded to see on call was Leah Murphy. Although Webber gave her a second chance, Leah wasn't the strongest of residents. She had the enthusiasm to learn, but this was overshadowed by the fact that she was totally inept in the O.R.

For instance, while arguing with Stephanie, Leah almost killed a patient by hooking their IV to their oxygen. In another incident, she drilled through a patient's leg and into the table because she was distracted by Arizona and Callie. On-call doctors have to be ready to be able to handle the pressure, and she wasn't.

Best: Alex Karev

Alex Karev looking serious at the hospital on Grey's Anatomy

Now, Alex was one of the doctors you would love to have on call. Why? Because he had the ability to stay calm under pressure. While Alex had his issues, no one can argue that he wasn't a good doctor. When he had difficult decisions to make, he confronted them head-on.

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An example of this was in "I Choose You" when he made a tough decision that affected the lives of newborn twins. Despite having issues with Jo, Alex put their fight on hold when his pager went off. Not once did he bring his problems into the workplace, which showed his focus was on his patients.

Worst: Vikram Roy

Vik refuses to take responsibility after causing a patient's death

Vikram has to be one of the worst doctors to ever grace Grey-Sloan Memorial. Not only did he endanger a patient after accidentally ingesting weed but one person died on his watch because he failed to examine the patient's nosebleed.

It is also believed he may be responsible for another patient's death after he cauterized a hairspray bottle and made it explode in the OR. Add this to the fact that he took advantage of his relationship with April and disrespected his attendings, Vikram was a liability and needed to go.

Best: Meredith Grey

Meredith Grey smiling

This Catherine Fox award winner has earned herself a respectable reputation in the medical community, going above and beyond to treat her patients. Although she is a mother to three young children, Meredith still finds the time to fulfill the duty of care she has to her patients.

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When Megan Hunt returned, Meredith reassured her that she was at her beck and call. When Holly Wheeler came to the hospital, Meredith supported the girl through her trauma. Regardless of the drama in her life, Mere makes sure her patients are her top priority.

Worst: Shane Ross

Shane Ross offers his services to Derek in the OR during his intern year in Grey's Anatomy

In the aftermath of Heather's death, Shane dove into his work to distract himself from his guilt. He grabbed any and all shifts available, going so far as to cheat the system so he could work more his hours.

However, since he wasn't getting any rest, Shane's mental health deteriorated and he jeopardized the health of his patients. More importantly, his irrational behavior also played a part in Alex's father's death. Shane was lucky to have a job after this.

Best: Arizona Robbins

Jessica Capshaw as Arizona Robbins in Grey's Anatomy

Arizona Robbins is also one of Grey-Sloan's best on-call doctors because of how dedicated she is to her patients. Everyone knows that Arizona is passionate about her job; they just didn't realize how much until Sofia's custody trial.

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In "Mama Tried," Arizona ended up leaving a very important trial because one of her patients was in danger. Knowing she could lose Sofia if she didn't fight her case, Arizona decided to let her go because she couldn't allow someone else to suffer when she knew how to fix it. Say what you want about Arizona, but you have to admire the dedication and commitment she has to her patients.

Worst: Sadie Harris

Lexie and Sadie talking in the morgue in Grey's Anatomy

Without a doubt, the worst doctor you could have on call is Sadie. She was underqualified, had no medical knowledge, and was negligent towards her patients. Sadie was also responsible for the death of Holly Anderson after she failed to notice the signs of a basilar skull fracture.

This sort of incompetence would not be tolerated in a hospital, especially if the Chief also discovered that Sadie cheated her way onto the program. Who knows how many more people would have ended up in the morgue if she was still on call.

Best: Cristina Yang

Sandra Oh as Cristina Yang in Grey's Anatomy.

The best person you would want on call is Cristina. Out of all the surgeons on the show, you will never find someone as devoted to the job as her. On several occasions, fans saw how extremely driven and passionate Cristina is about medicine, especially cardiothoracic surgery.

Many of the other attendings also recognized her talents, with Webber believing her to be the best in her class. Since Cristina is always at the hospital, you wouldn't even have to ask her to take a few extra shifts. She would live in the hospital if she could.

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