Yes, of course humans can become 100% perfect, but the question is how long will those who are perfect, remain perfect? It all depends on how you define 'perfect.' I believe a person is perfect when their good-will intent is to help someone who's in need, but without the purpose of regaining anything back from that person. Being perfectly honest and willing to accept correction from someone else, to me is perfect. Training your mind to think positive, and use a positive approach to solving a problem, that to me is perfect. Making the choice to quit bad habits is also a perfect choice. Humans can indeed be perfect.