Adjustable bed sides allow you to use mattresses of different thicknesses.
This is the first purchase at IKEA that I semi-regret. It was only $150, which is a bargain for a big wardrobe. My whole house is Malm and Hemnes (beds and dressers). So I was surprised at how the doors didn't line up correctly and their was a gap in the back where the center support piece meets the top piece. Also, the right door catches against the middle door so you have to push it shut so that it's flush. I've put at least a dozen IKEA furniture pieces together and this is the first one that didn't line up well. The good news is that it does look very nice all put together and feels pretty sturdy. It's not bad if you're on a budget, but if you have the cash, I would trade up to a nicer unit.
I bought this on sale and its great. I use it as a game room storage. It fits a ping pong pitching robot, all my paddles, a 12x12 net, and a bunch of my wifes storage junk. Not sure how much it is normally, but this is the best deal ever.