The very important and controversial issue of Sam's shirts!!
We all know that Sam has been wearing the same style of shirt for 8 seasons, well it's high time that he changed it up.
For one, the style is dated.
Two, Callen is supposed to have less belongings than Sam, yet he's been shown to have more clothes. So on a slightly more serious note, Sam having only one style of top is inconsistent with character development. It also makes him more memorable, and for a guy who changes his route to work every day, this is not good.
In S1 Sam did mix it up a bit more, but since S2 he's pretty much only worn different colours of that tight top. I say the NCIS:LA wardrobe team should try something different. I also envisage a scene with Callen teasing Sam about only having the one type of shirt. lol