Ah, those videos don't remind you to sacrifice a goat every Tuesday to make sure that doesn't happen. Little known secret of maintaining sanity while using Unity. Seems you missed yesterday's sacrifice, so you'll probably be pounding your head against a padded cell by Friday. Tough luck!
Just finished recreating the Roll a Ball tutorial on their website, less than a minute ago. Countless videos, poring over code, what open/close curly bracket did I miss that's messing everything up, troubleshoot, troubleshoot, alt tab over and over and over, test, play, learning things, and finally several hours later I produced a minigame in which I roll a white ball around a plain blue box collecting spinning yellow boxes, and there's a basic UI that counts the boxes as you roll over them and then says "You Win!" (white, arial/helvetica for extra snazzy flair) in the center of the screen when you got the last one. I'm so proud of myself. I don't know if that's meant sarcastically. ... Damnit, where do I get a goat to sacrifice? Freakin' cults, always assuming you have money to buy livestock with.