Transcript for 'American Idol' Ends: Fantasia Barrino, Ruben Studdard and Justin Guarini, Live on 'GMA'
Carrie Underwood, Keith urban from the big finale. One of the great moments from last night "Stop dragging my heart around." She was awesome launching the careers of so many talented performers over the course of its 15 seasons. We're going to talk to our star-studded panel of "Idol" alumni in a moment. First here's Chris Connelly taking us behind the scenes. Reporter: Who will become the next "American idol"? From its 2002 debut "American idol" was star making. Kelly Clarkson. Reporter: And heartbreaking. The journey ends. Reporter: Where sweet showbiz dreams came true. Jordin sparks. Reporter: Or collided with harsh reality. The day the music died. It just did. Reporter: Its 15 seasons seemed to reshape the entertainment landscape and launched out of nowhere sensations like Kelly Clarkson. And Carrie Underwood. âª Here in the dark âª Reporter: And you didn't have to win to have an impact. Adam lambert hit big âª so what do you want from me. Reporter: Clay Aiken won a million hearts and Jennifer Hudson won an Oscar. âª Love me âª Reporter: Viewers enjoyed the flash enafoibles of its contestants. âª She bangs âª Reporter: Along with the ever unpredictable behavior of judge Paula Abdul. But not everyone loved it when Simon Cowell seemed to cross the line. You did -- Ryan Seacrest. Don't call me sweetheart. Sweetheart. We don't have that relationship. Reporter: Or this conversational exchange. Do we have a bigger stage this year? She's like France. Reporter: Here's three things you might not know about "Idol." Such soon-to-be successful sings as Coby Calais and lady antebellum's Hillary Scott say they never made it past their "Idol" auditions âª I need you now âª She did make it to Hollywood week and got cut and got nominated for a best new artist award. âª Reporter: Over the years contestants thought some songs were cursed. When people did the song "Feeling good" by Nina Simone they went home. Two contestants sang it and they both went home. Reporter: In a first person look back on his 50th birthday Simon Cowell would confess his own inadequacies. You feel that everyone is laughing at you behind your back. He'd write about himself. That's because they are. Okay. Reporter: There were more tears than laughter as "Idol" left the stage for good last night. The 21st century's most commercially significant show thus far and the perfect place -- âª for a moment like this âª Reporter: For "Good morning America," Chris Connelly, ABC news, Los Angeles. What a great look back. We've got the "American idol" stars joining us from los Angeles, season three winner fantasia barrino. Season two winner Ruben Studdard. First season's runner-up and no show ever like "American idol," Justin Guarini and Kate Coyne. The reality talent competition didn't exist before they re-created it and made it a sensation and made so many stars in the process which really took a part from the other shows out there right now that still haven't produced that kind of Kelly Clarkson, you know, Carrie Underwood, those people have not come off "The voice" yet and that's what "American idol" did and made stars out of people like Simon Cowell. No kidding. That's what I was going to say. Different from the other shows that tried to follow. What do -- is it just that there are so many seasons that they just have a better eye than the other show? What sets it apart. They've had a longer run at it but I think in those early seasons that original judging panel having -- having the expertise of Simon Cowell because the thing about Simon was he was mean, but more often than not he was right. So, that sort of impeccable taste clearly creates stars. Let's go out to our stars right now, fantasia, take us back to your first moment, that first moment of your first audition. Well, I'll have to say there was a lot of powerhouses in that building in Atlanta. A lot of people that were very, very talented and so, you know, I was very nervous and I wanted to do my best. I always heard a lot about Simon. Had never seen him. You know, and I went in and just gave all that I had. I want to hear from Ruben. Hi, Ruben. How are you? Great to see. You hey, how are you? I want to ask you about your first "Idol" stage moment. What do you remember most? I just remember, you know, coming on stage and, you know, being in the room with, you know, the fans that were in the room, how excited they were and I remember first coming into the building watching everybody outside waiting for their chance to get in the building was just -- I couldn't believe they were all there for us. And Justin Guarini, we've got to talk about Simon here. How do you get used to dealing with Simon? You know what, I was very fortunate to be well received by Simon for the most part. But, you know what, at the end of the day I think you nailed it on the head. He is honest and he'll tell you himself, look, if I tell these people, oh, you know, you were really great and they continue to work for years at a craft that they're never going to go anywhere in they'll waste time and money and effort and he'd rather nip it in the bud. Hey, I completely agree, Justin and want to tell everybody Ruben has a single out "Ain't nobody love you." Released on itunes, how all of your lives were changed by this iconic show. Wouldn't you agree, Ruben? Absolutely. You know, I've been wanting to do this job since I was 5 years old so "American idol," you know, despite everything I tried never worked and "American idol" is the thing that worked so I appreciate it so much. Worked for you, fantasia. Went on to brood. Got a fifth album on the way and last night got to perform your new single "Ugly." Anything you want to say to the "American idol" family that helped launch you? Yeah, I think I would just say thank you. You know, it opened doors for a lot of talented young people. It's bittersweet to see it go away. I'm praying that it will come back but I thank them so very much. The thing about me I've always been fantasia. I might be the rebel out of the whole bunch. There's been a lot of ups and downs but I never have given up and I will continue to fight and I just thank them for seeing something in me that I probably wouldn't have seen in myself. I love that spirit and your authenticity. Justin, how about you? How has your life changed because of "American idol"? Oh, mine, I mean, how has it not changed because of "American idol"? I spent the past five, six years on brood. Ooh. I have a wonderful commercial where I play a character, little sweet for diet Dr. Pepper. I leave on Sunday to go to Sweden for 11 days to work on my next album so life is good and I have "American idol" and all these wonderful people who came after me to thank and for all the work that they have done, because I'm truly blessed. Let's do a lightning round game. Yeah, absolutely. Whoever knows the answer, shout it out. Uh-oh. Who had the most stage fright? Who had the most stage fright? Did any of you have stage fright. I don't know who had the most stage fright of all of us? Or anyone you knew. I don't know. It felt good by the time we got to the live shows. Everybody got really comfortable. I always get nervous before every show but by -- How about your favorite moment on "Idol" that no one ever saw. Oh, my favorite moment on "Idol" that no one ever saw was the prayer that we would have in the coke lounge every episode. That's sweet. Yeah. I mean, no, we did. We prayed together. That's beautiful. And finally we'll end it with a little Simon moment. What do you guys remember being like the worst thing that Simon ever said to you? Wow. Or just someone. What was something he said that made your jaw drop. I didn't get a lot of tough things but one thing he said and I was like, I don't think you ever put those lips to better use, I was singing a song. Wow. Just towed the line on that one. Towed the line. And compliments have a little edge. You guys were great.
This transcript has been automatically generated and may not be 100% accurate.