Lol Bieber did not have LL done, his media people and outfitter are just absolute gods at making him look tall in front of the camera and from certain angles. Baggy long tees, big jackets, tall sneakers, baggy drapey hoodies, he does it all. Bieber's dad is 5'6 and his mom is 5'0 I think? So it's no surprise he ended up 5'7, and I don't think he got LL to reach that.
If you see videos of Bieber walking on the street with other people, it immediately becomes obvious that he's not very tall. Still, it's so strange to me that people can have such different proportions. Jonah Hill is only an inch shorter, and even after losing weight, he looks very short compared to someone like Bieber. And they're less than an inch apart!
For example, this is the wiki photo for Bieber
Because of my height obsession I can normally pinpoint someone's height based on their chest and torso alone, and honestly, if you showed me this photo I would have a hard time believing he's any shorter than 5'11.