Restart Button on tests

Hello Khan Academy,

Why isn't there a restart button on tests? I feel that making a student retake a test because they got one wrong and lowering their progress is quite counterproductive. My daughter spends an entire day doing one unit. She is always complaining about how there is no restart button. Retaking a test is a massive waste of time, especially if the student understands the concept but didn't understand the question. Every reply to these types of feedback I've seen, is  "teachers wouldn't be able to track students progress" or "We are trying to encourage a growth mindset." All of that is total bull. When students see the low score because they couldn't restart the test, it lowers their self esteem. Honestly, you people think you're helping students, which you sort of are, but for the most part, you all are frustrating them and their parents/teachers to a terrible extent. I really feel like you should take this into further consideration. And this Mastery Plan where the students have to take the unit test to level up is bogus. And when you get a question wrong on the unit test, your progress lowers. Please, take this into further consideration.