The line borrows its punch from Thor, the Marvel hero known for dramatic battles and stubborn determination, so telling him you are done flips that larger-than-life energy into an everyday joke. Short reaction clips like this spread through meme edits, gaming montages and social videos, where a recognisable name makes the joke land instantly even without context. Its appeal is not a complicated backstory but its versatility: the same three words can close a defeat, a debate or a long day, which is why creators keep reusing it as a quick, shareable sign-off.