See inside to know what's happening How Scratch Works (running codes) 1. Scratch can run the whole script in one frame but not in some cases i'll mention below 2. Repeat block runs the codes inside it multiple time depending on the input. Each frame, it'll run the whole script in it once. 3. Custom block: Without ticking "run without screen refresh" custom block is just like a customiziable function. If you had multiple codes to make the sprite do something, and you want the sprite to do it multiple time but you need to change some inputs a little bit but there's no pattern between those values then you can use custom block with your own inputs. 4. Custome block: With ticking "run without screen refresh", the custom block will run every codes in it in 1 singular frame, even when it contains repeat blocks that normally run in multiple frame. 5. The only next reason that sometimes the script should run in 1 frame but it doesnt is because of lag or too much codes/looping run without screen refresh custom block. Well that's all. Lemme know what do you think and what did i say that you think it isnt true Bye ~