What exactly happens when a fighter 'gets put in a submission' in MMA like Khabib vs McGregor?

ever felt your arm turn into a boiled noodle when some bloke twists it the wrong way — but on steroids and in slow motion — yeah, that's a submission pretty much starts when one fighter latches on to an arm, wrist, leg or neck and cranks it just enough to make the other go "okay okay okay" or starts seeing stars instead of the cage floor but doesn't let go. the tap is the magic word: two slaps on the mat or body, the hand, or sometimes just a verbal "tap", and ref blows the whistle, fight's over, like a circuit breaking before the fuse blows.

How does that even happen though? I've seen a hundred Khabib finishes and still stand there watching the replay like it’s a murder mystery where the victim chose to tap. Let’s take May 6, 2018 in the MGM Grand Garden — UFC 223 main card. Khabib Nurmagomedov vs Al Iaquinta. It never went past the first round, but inside those 5 minutes Khabib snaps on a neck crank that looks like a bad bass tackle. Iaquinta never buckled; his chin stayed high, he weathered strikes, even tagged Khabib once. Then suddenly the Dagestani tucked his head under the right arm of Khabib who already had both hands locked around Iaquinta’s neck like a vice. No guard, no space. Iaquinta tried to stand up once, twice—just leaned into Khabib’s chest instead. Then his arm flopped over the top rope, giving Khabib an extra lever. From that moment Iaquinta’s head was no longer a head; it was just a weight attached to the end of a choked spine. You could see his eyes darting side-to-side because he couldn’t turn his skull; the angle alone was screaming enough. Then his right hand came up—once, twice—two weak slaps against Khabib’s arm. The ref didn’t even need to look at the cage floor: two smacks equal surrender. Cage side judge stopwatch read 3 minutes 30 seconds when the ref stepped in. Not the flashiest triangle you ever saw, yet the cleanest textbook neck crank finish in modern lightweight history.

Yeah but like… what if the guy doesn’t tap at all? I’ve seen loads of Khabib finishes and some of them just go limp, no tap even though they’re getting choked or their arm’s bent weird. Does the ref just wait forever until they pass out, or is there a time limit before he stops it anyway?

i still remember the first time i saw a guy get choked out cold in the 90s, not even a tap—just this little cough, then sleepy eyes rolling back. took me years to understand why refs don’t always wait for the lights to go out. here’s the thing: taps are the golden rule, but the body’s clock runs different for everyone. if a fighter goes limp or if their breathing shuts down—even if there’s no tap—the fight stops. referee’s eyes are on that pulse, not the tap. in the old days it was all about the crowd screaming “he’s out!” then the ref pulled them apart. now? refined. automatic. corner jumps in the second the blood flow to the brain drops. the grey zone is when someone’s conscious but refuses to give the tap. maybe pride, maybe they’re in a zone, maybe they think they can grit it out. but the rulebook says: referee discretion rules. at ufc 229 when Khabib choked Poirier unconscious, Poirier never tapped—he just gurgled once and went night-night. ref stopped it at 2:06 of the third. no hesitation. so here it is: in short, the fight ends the moment the ref sees danger, tap or no tap, conscious or not.