I don’t know where it comes from, but it’s a clone trait in a bad script, so be vigilant in your art.
This person, ostensibly the center of the script, whose story it is, is no one special, has a job, some friends, family, things they like to do.
And then something happens, and the person gets dragged along by the situation, sort of like a spare audience member in the story, watching drama created by other characters and occasionally dispensing an opinion about it.
This is not correct. It’s not the protag’s job to watch the movie for us. The protag must be interesting and active enough to deserve to be watched on their own merits.