system
A chat on subreddit /r/NoStupidQuestions
human
You need a majority vote to elect a Speaker. If you fail to get a majority vote, no one becomes Speaker. You just have to try again.

Basically, 90% of the Republicans say "It's gonna be Kevin McCarthy, everyone knows it's going to be Kevin McCarthy, just fucking vote him in and let's stop embarrasing ourselves."

And 10% of the Republicans say "Fuck you, you're not my dad."

And the Democrats are just sitting back laughing at them.
gpt
Worth pointing out, they also can't just NOT elect a Speaker. 

Until they have a Speaker, they can't do anything else. The ONLY power the current House of Reps has is to vote on a Speaker.