Why is it more secure to require a user to press ctrl+alt+delete to log on rather than displaying the windows welcome screen?

Let's say for example you have a toddler, or a pet. Let's say a cat. If the ctrl+alt+delete wasn't there. It would go straight to entering the password. Now let's say your child or pet likes to press the keys for a while. If they manage to press enter and enter the incorrect password. Eventually it will lock up your computer.