Does someone decide what we listen to? How Spotify’s algorithm works and what we know about its real power

How do we discover new music? It used to be mostly through friends, record stores, and radio. Now, friends, some radio stations, and music platforms still play a role. Spotify’s annual wrap-up is an ideal time to see what new music has reached our ears. The European Union is funding a project to “audit algorithmic music discovery” because it believes there may be bias and a lack of transparency in this process.

Spotify and other platforms now seem to be the main players in the music world, both for listening to and discovering new music. But Lorenzo Porcaro, a mathematician, researcher at Sapienza University of Rome, and director of the European project to audit algorithms, believes it’s not that simple. These are his main points from a conversation he had with EL PAÍS at the Mozilla Festival held in Barcelona in early November.

1. How we really discover music

It depends. Social media is very important for young people. “They use TikTok, YouTube, and other platforms a lot,” says Porcaro. “On streaming platforms, even though they’re marketed as the place to discover music, that actually happens less.” The relationship between artist and audience on social media is key today, the mathematician adds: “They upload a new song or say, ‘My track comes out this Friday, go listen to it on Spotify.’”

2. Does someone decide what we listen to?

Once inside Spotify, are we encouraged to listen to something? “It’s hard to know for sure, because from the outside you only see the final result,” says Porcaro. In some cases, there are examples that seem logical, such as recommendations based on geographic location for major music festivals. “I doubt that someone in the U.S. would see songs from [Italy’s song competition] San Remo or Eurovision. They know that the domestic market is very important in some countries. In Italy, for example, I think 90% of the music listened to is by Italian artists. That’s one of the highest percentages in Europe,” he adds.

3. Why we think there’s a conspiracy about what we listen to

It’s possible that things happen behind the scenes that we don’t know or control, but their impact can’t be measured from the outside. That’s why conspiracy theories arise. “Without resorting to conspiracies, I start from what I do know,” says Porcaro. “The major labels are the most interested in promoting certain music, just like with radio: on the radio you hear what’s commercial. We also know, because it’s public information, that the major labels have invested heavily in streaming platforms.”

But the fact that the algorithm recommends mainstream artists doesn’t mean it’s influenced by some big company: “The recommendation logic is very much about performance: if there are 50 people in a room and they all listen to Bad Bunny, if someone new comes in and I recommend Bad Bunny to them, will they like it? I don’t know, but if everyone here is listening to him, why not recommend him?” the mathematician explains.

Spotify has just announced the most-streamed artists in Spain for 2025. It’s impossible to know whether this reflects Spaniards’ genuine taste in these artists, or if the platforms have somehow influenced their listening habits. “That’s the biggest problem for me about working with these systems: very little is known,” says Porcaro. The music industry market is centralized around the major labels. “Behind streaming, there’s a very long history that influences how music has been distributed. While social media emerged from nowhere, as a new technology, the music industry has been operating for years and wields enormous influence,” says Porcaro.

4. How does shuffle play affect it?

Shuffle play is a common way to listen on streaming platforms: a simple algorithm chooses songs from a pre-made playlist. Could it be that this mode subtly favors some songs, or that others are overrepresented in popular playlists?

“It could be,” says Porcaro. “Random appearance doesn’t mean that every song is recommended once. It means you don’t choose. Talking to people, many are struck by the fact that ‘random isn’t random.’ That, for me, is the point. The word ‘conspiracy’ is often used to cover up things that might actually exist. We don’t know what happens at that moment when we all get recommendations, but if many people are talking about it, there must be a reason,” he adds.

That is the focus of Porcaro’s research: “I try to rely on the theories of people who don’t come from technical things or understanding algorithms, but from lived experiences, which also carry weight.”

5. Like the radio, but personalized

Streaming platforms were born as a service where, in theory, all the world’s music was available at low prices. “But by incorporating personalization and algorithms, today’s experience is quite similar to the radio of the past, only tailored to your tastes,” says Porcaro.

And what is the logic behind radio? “The latest [music]. This is very noticeable on Spotify. When people listen to music, they want to know about what’s new, to stay up-to-date. It’s part of how music culture works. I don’t think the platforms are inventing anything new; they’re reinforcing dynamics that already existed,” he adds.

6. What should someone starting out in the industry do?

If streaming platforms haven’t changed the industry that much, it’s likely that up-and-coming artists shouldn’t change their practices much either, Porcaro believes: “When I talk to emerging artists, I see that these platforms sell the illusion that you can become famous thanks to the algorithm. Before, when you were starting out, you had to work hard in your city, play gigs in the surrounding towns. That’s how you become an artist, not because you make a viral song and it suddenly becomes a smash hit.”

Social media has definitely changed the game and has become somewhat essential: “Now it’s important to be connected with your fans. Whether that’s good or bad is another debate, but as an artist you can see what you like, and everyone decides if they want to do it,” Porcaro explains.

7. And what you shouldn’t do

There’s a big difference between social media and streaming: “For platforms, you’re just another user. They tell you, ‘Give us your music, give us your data, and maybe one day you’ll become famous.’ It seems like a more passive game to me,” he says.

It’s part of the marketing ploy on these platforms, where artists are also users: “You open Spotify for Artists [an internal Spotify tool for artists to view their statistics and decide on actions], you try to access a playlist, and you end up playing the game they’ve set up. In the end, artists are also Spotify users. This is precisely what needs to be deconstructed. I’m not saying you shouldn’t use it, but you have to do it consciously and not fall into the illusion of ‘maybe I’ll become famous thanks to this’,” he adds.

8. Big changes don’t depend on a platform

Streaming has been touted as the great solution to piracy. “It’s hoped that some of that recovery will also reach the artists, which would be only fair,” says Porcaro. “The issue is redistribution. This technology reflects the same dynamics as previous ones: who gets the most exposure. What isn’t redistributed is the most problematic aspect, not the technology itself.”

“I’m optimistic about music,” the mathematician concludes. “Because often what ends up standing out comes from a subculture that then becomes more dominant. And then others will come along; they always do. It’s a difficult mechanism to break.”

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