Confused about error handling

main.rs

use std::process::Command;

fn main() {
    println!("{}", git_name().unwrap_or("".to_string()));
}

pub fn git_name() -> Option<String> {

    let output = Command::new("git")
        .arg("config")
        .arg("user.name")
        .output() 
        .expect("Couldn't run git!");

    if output.status.success() {
        let s = String::from_utf8_lossy(&output.stdout);

        print!("git config user.name: {}", s);
        Some(s.to_string())
    } else {
        let s = String::from_utf8_lossy(&output.stderr);

        print!("git config user.name failed! {}", s);
        None
    }
}