Goldfish are hardy fish, of course, which is probably why they are viewed as "hard to kill" and good beginner fish, but it would be great if people would know how huge these grow!!

One of my friends had a cute fantail called Helena, when she was a kid, the fish lived in a big glass on foot (much like the one Minde keeps one of her bettas in), and I do remember this fish living for a few years! But she didn't grow too big either way. Which is most likely why people view them as "easy to care for" pets. (they are indeed, especially if you provide enough space and filtration.)

That's pretty big for being kept in a bowl! But look at that, your uncle actually bothered to care for the fish, even though it wasn't kept in the best setup Caring is more than half the effort!