Anybody can change their mind

That is another way of saying that things went wrong and you want to fix them or start over. That is understandable at any time, but more so while attempting a tutorial. One way of handling that, as we pointed out earlier, is to quit GnuCash without saving. What if you have already saved a transaction and had a thought after that? Yes, GnuCash allows you to change your mind even that late in the game.