Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Surprise!!

These are just shelves, so I can't get too excited or upset. I received them a couple of days ago and installed them in my garage. Not to difficult . . . find a stud, drill a hole and attach bracket. No problem so far. I came home tonight and one side of one of the shelves had come unattached from the wall. I couldn't believe my eyes, that is, until I realized that the bolt head had snapped off (the bolts "bodies" were still securely in the stud). I guess I had over tightened (by hand) or perhaps the hardware was just too cheap? I have to move the entire shelf now which isn't the end of the world, but now I'm waiting on the other shelf to fail. btw - for those wondering, I only had about 30 lbs of stuff on the shelf when it fell (well within the documented limits).My recommendation . . . if you buy these shelves go invest in some $2-3 hardware from the local hardware store, or you might get a similar surprise.