Liam had forgotten his hair straightener when they went to work with RedOne in early 2011 and so he just let his hair air dry. After that they were constantly moving and so Liam just decided not to straighten it anymore.
Thank you RedOne, trendsetting in the studio, trendsetting in the beauty world
I try to stay as far as I can from these Bieber threads, but he's just so damn annoying...it's not like Bieber's hair was something never seen in the first place