Some people will burn out and give up. Some people will get cocky and rest on their laurels. But others will study smarter and harder to pull up a mediocre first semester. Some will get involved in extracurriculars, which may or may not affect their grades. Some will search diligently for a 1L summer job, while others will find a job quickly and others won't bother to make summer plans until the last minute. For all of these reasons, second semester 1L year is still intense, and (good for you or not?) grades tend to sort out differently at the end than they did 1st semester.