There seems to be some quality control issues with the Arc fit. I have two that fit nice and tight, one that practically falls off with a slight bump.
QC with cases in general seems poor across almost all brands. My new Phone Rebel has a gap between the metal camera surround and the TPU body on one corner. This showed up after taking the case off just a couple of times. It’s a perfect spot to trap every type of dust and detritus. Now I have to decide if it’s worth the hassle to deal with PR support and ship it back for a replacement. Ugh.
So this year I had a defective Arc, Süti, Otterbox, Phone Rebel, Pitaka, and a number of Benks. It’s been a banner year. 😂