Fuller has not necessarily been terrible-he has broken up 50% of his targets. However, at the same time he has given up two touchdowns that have been directly linked to him.
Fuller was beat by Geronimo Allison and Tyler Lockett too. It is not like Antonio Brown, and Odell Beckham beat and those are things that happen.
The fact is that there are a lot of strong qualities to Kyle Fuller. His length, athleticism and ability to tackle all come directly to mind. However, one area where he will always struggle is his ball skills.
Some quarterbacks who are daring such as Russell Wilson and Aaron Rodgers can take advantage of Kyle Fuller because of that. If you put a ball up there where both players have to make a play on it, he can struggle to do so.
As we move on and see a quarterback like Sam Bradford, or a more conservative passer, we will see if the struggles continue.