Ok but you don't DIE if you get hit once in street fighter you can still theoretically come back from any amount of health without relying on tons of human error
Is there any point in playing a game that you can't win anymore? And if you just quit, the whole point of Kahoot (being a study tool) is completely eliminated
Jokes aside, this is just how quizzes work. If you get one question wrong and your opponent doesn't, you lose. If there are (e.g.) 10000 points up for grabs, then a player who gets 10000 points statistically can not lose. It's not a flaw with Kahoot so much as it is with the entire concept of a quiz where everyone answers the same set of questions (if you can even call it a flaw). And just because you can't win, that doesn't mean that there's no reason to keep playing. You are competing with the entire class, not just whoever is in first, so try and place higher than your best friend who's sat in the back corner instead of continuing to compete with the nerd on the front row.
An actually-flawed quiz would be something like Mastermind, where you are on a timer to answer all of your questions, can't guarantee that your set of questions are going to let you get through the same number of questions in the same amount of time, and you aren't allowed to interrupt the host (meaning you can't claw back time lost due to variance in question length by figuring it out before the question is over). This is
actually unfair design, as players aren't guaranteed to be on an even playing field.
Quizzes aren't exactly the only games like this either. For example, it is very, very common in high level snooker for you to lose an entire frame off of one (often very small—far smaller than getting a question wrong in Kahoot, and much more like guessing a second or two slower than whoever you're tied for first with) mistake. You can't go up and influence your opponent's cuing or change the positions of the balls when you aren't at the table, so you are forced to sit there and watch as Ronnie O'Sullivan cleans up. Similarly, if two strong chess players play against each other, it is common for one positional mistake or incorrect move order to be the difference between a draw and a loss, and one blunder is all it takes to turn a commanding winning position into an entirely lost one.
In both of these cases, if your mistake leaves your opponent with a good enough position, your ability to come back will depend entirely on your opponent cocking up somewhere. Does this make snooker and chess bad games? No, of course not. It's just a different room-for-error threshold than a game with more variance. And for a quiz, you ideally want as little variance as possible, because you know what feels worse than getting one question wrong and losing because of it? Getting every question correct and then losing to someone who didn't because of something completely out of your control.
