When you scroll to the bottom of a release description, you often find a block of short lines that start with words like Produced by, Arranged by, Recorded by, Mixed by and Mastered by. We read them as a rough map of how a song went from an idea to the finished file you press play on. Each line names a job, and each job comes at a different point in the process. They are listed separately for that reason, not because the credit block is padded. Once you know what each word means, the block stops looking like a wall of names and starts reading like a sequence.
Here is how we read the first three. Producing means overseeing the project as a whole and shaping the finished release, so it is the broadest of the lines. Arranging means building the musical parts around a song that has already been composed, such as deciding which instruments play what and how the sections fit together. Recording means capturing the performances, whether that is a vocal take, an instrument or a programmed part. None of these lines tells you what the song sounds like. They only tell you which role a named person is credited with, and wording can differ from one release to the next.
The last two lines come after the performances are captured. Mixing means balancing all the recorded parts into one track, so the vocals, instruments and effects sit together at sensible levels. Mastering is the final preparation of the finished mix so it plays consistently across streaming services and different devices, and it is usually done by a different person at a studio. Because these steps happen in order, they get their own lines. If you see Person A on several of them, that is common, especially when an act handles much of its own release, and it does not signal an error. It also does not tell you how much each person contributed, only the role credited.
It helps to compare these lines with the separate ones for composing and lyric writing, which describe writing rather than production. A song can be written by one group of people and then produced, mixed and mastered by others, so the two blocks answer different questions. To confirm any detail, start with the credit block in the description, then check the credits view on the streaming service, and then look at the act's own announcements. Be ready for limits: some descriptions credit only certain stages, the wording varies, and a credit line never describes the sound.