Why do people leave homework and projects at the last minute?

It seems like everyone I know leaves some kind of homework and project until the night before it is do. It all comes back to laziness or what we have learned from siblings. My brother, Kevin, left most of his stuff off until the last minute, but he always got straight A's in school. So it was kind of stuck in my head that I will do well no matter what, but when ever I left things off it was always so nerve racking doing this big assignment at 9:00 p.m. I countlessly see people all over school going to bed late because he or she keep on leaving it off until the night before it is due. I don't know if poeple have had the same experiances that I've had, but this slacking off is everywhere. People think, "Oh, I have time to do this so I'll just leave it off when I feel like doing it," but how is it the that "feeling like doing it" so often happens at about 11:00 P.M. huring to get it done before it is do the next day? I'm even doing it right now! We need to realize that we or people around us are slackers and need to realize what we or others are doing to their selves. We need to make goals and say that we will do the assignment the day we get it, so we dont stress our little hearts out. We cant do things like this in college or we will never servive.