Actually, I disagree. Junior developers usually have very poor judgment about things. They might be smart and able to create a mountain of code, but it will be the wrong code, and will not be understandable by others who have not worked on it - i.e., unmaintainable. And code by junior developers tends to be very brittle - one little change to things and it breaks. Of course, these are tendencies among groups - everyone is an individual, so these are not rules - just tendencies.