That's good advice. Before you learn how to make a dish, you must learn various ways to ruin a dish. You can read all the books in the world, but only dozens of bad omelettes will teach you how to make a good one.
There is one musician on YT who said that he is simply doodling away on his groovebox frequently and that more than 90 percent of the results are shitty. But from those ideas that are somewhat decent he develops his music.