Have you ever seen someone post a picture of their overcooked steak or their burnt toast on Facebook? How many status updates have you read that say, “Mother fucker: I Didn’t get a personal best today!”  I don't imagine very many. People don’t boast about their fails. They post pictures of their perfectly-cooked poached eggs and bacon sitting atop a bed of fresh greens, topped with delicious-looking guacamole and a pinch of paprika. And in the idealized Facebook world, every single person on your newsfeed seems to have just set a new personal best. Meanwhile, in the real world, you’re at the gym pissed off that you haven’t hit a personal best back squat in six months. The truth about...