Basically something is said or posted ironically, meaning that the speaker is humorously mocking someone or something. Over time, the use of the phrase or content evolves either in an online or irl community, like most humor or inside jokes. As this process occurs, the phrase/punchline become further removed from its original ironic use and becomes funny on its own, removed from any context of irony or commentary on an outside context. Using the previous comment’s example, a group of people might begin using the term poggers ironically to both mock its use on twitch and to annoy their friends, as the usage continues, the phrase simply becomes a common phrase, retaining an association with humor, yet detaching itself from the origin of the phrase