Yes, a mistake, but I can´t say what is wrong. I feel some hand shaking, my eyes are pushed to the top right angle, maybe because of the light. Compositionally this is perfect, I think, and the thick border is a great idea. But, there´s just something wrong with the focus and light here...I don´t know, but it never made me go for more than a 5 here.
Looking forward to see you in the other challenges.