Transcript for 'American Idol' judges Lionel Richie, Katy Perry, Luke Bryan on new season
I stand up. You're going to Hollywood. Thank you so much. Every year I tell myself I won't cry watching these "American idol" auditions. And I won't. Shut up. Reporter: Nope. Not happening. And I want you to understand. We got you. It baffles me that some of these kids will come in so raw, beautifully talented, and no one's ever told them. Reporter: How can you not love the teen from Nepal who sounds just like Bob Dylan? Take a deep breath and give it to us. I set out on a narrow way Reporter: The Alabama garbage man setting out on a broken road. The broken road You're going to Hollywood. Reporter: And the subway performer. I rise up teaching us all to rise up. I rise up Yes, even after all these years "Idol" delivers. Its secret sauce, finding These people come from the nooks and crannies of America. Reporter: Wrapped in compelling stories. I couldn't listen to music growing up because where I come from music is prohibited. A lot of artists are working from a place of pain. And from sometimes great pain comes great art. Reporter: Those diamonds in the rough discovered across the nation thanks in part to great judges like Katy Perry, Lionel Richie, and Luke Bryan. We're just trying to set you up for global overtaking. What a unique artist you are. They don't need any more criticism. They need a hug. They need you to go, okay, now we have you. And I think once we start breaking that ice with them then they can go become what they came here to be. Reporter: The magic is in the stories and in the singing, which toes the line between the truly awe-inspiring. and the duly cringe-worthy. the show's been hitting all the notes for nearly 20 years. For those of you who might not have even been born when it premiered, here's a quick recap. Hello, Kelly. Hello. How old are you? I'm a big fan of you, by the way. Jennifer Hudson from Chicago, Illinois. Yes, sir. Hi, Carrie. Hello. Are you nervous? A little bit. Hi, guys. How are you? Adam. Hey. Adam, Adam. What's your name? Scott Mccreary. Scottie. Reporter: It's not always just about the contestants. It's also about these guys. Dreadful. Pathetic. Hated it. Everything about it was Reporter: The celebrity judges. And that's just about celebrating the effort of -- Reporter: And their infamous feuds. From Paula versus Simon to Nikki versus Mariah. We're trying to help her as opposed to just talk about her outfit. Of course. Reporter: Though for the last three seasons on ABC they seemed to have reached a harmonious mix of sugar, spice, and soul in Katy, Luke, and Lionel. We are so invested in this show and the outcome and these people's dreams. Like this is no joke. This is not just a job, y'all. This is like a passion. We check our egos at the door. We're there to try to find huge stars. It feels very generous. And hopefully very genuine. I mean, this is where we get to take all of what we've learned and like give these kids some kind of shortcuts. There's a calm before the storm Reporter: Shortcuts perhaps but for so many hopefuls facing the hard truth it's half the battle. I don't like it. I don't like your attitude. We want to check them early. It's very important. Because you can be the greatest singer in the world. Your ego killed you. I don't really think you're going to make it in Hollywood. Reporter: Now, they won't all make it to Hollywood. And even if they do, winning isn't everything. To watch dreams unfold in front of your very eyes is very inspiring. I mean, I went home after auditions and practiced on guitar and piano more than I have in years just because music is just so inspiring. Reporter: Another season of singers -- well, mostly singers. Wishing upon hope to become one of the very few to join the ranks of music's most recognizable voices. What have you learned about yourself? It was always the so never forget why you're doing what you're doing. It's my job to teach them. But they have to understand that it does not come with a diploma. It comes with hard work. MM. The diploma at the end is when the crowd says we love you. And we can't guarantee that. But you do help people find their voice. Absolutely. It's all for you Reporter: For "Nightline" I'm Adrienne Bankert in Los Angeles.
This transcript has been automatically generated and may not be 100% accurate.