Yup! As WS and I say, "That one's a drillah"!
You can do better. Of course, if you repeatedley set one bad rivet after the next, you should keep a marginal one if the repeated setting process is detiorating the neighboring material to the point of no return.
These neighboring rivets look good, so it is possible to do properly.
Now, from the looks of this rivet I would say that you were just simply not sqarely set on the rivet head.
You seem to be trying so intently in getting closer to the main rib that you in fact got too close!
In driving these rivets with success, it is VITAL that the set be in line with the shaft of the rivet. Ideally, the shaft will be perpendicular with the surface of the material. This isn't always the case in thinner material, but with these, it is.
Take the rivet set (removed from the gun) and a AN470 rivet and sit in front of the TV and play the rivet on the business end of the rivet. Look at the way it sits on the set and notice that it leaves an edge all around the rivet exposed. You need to keep this image in your mind's eye before pulling the trigger! Keeping the set in this position will give you PERFECT results EVERYTIME!
Drill this one and try it again. You would probably be fine with it, but these are really not that hard to set. You can do it!
Also, if the hole gets too large you can pull out your squeezer and fatten up a longer rivet. This essentially creates an oops rivet and makes it easier to buck what is really a longer rivet.
Do ya knowwhatta mean?

CJ