He had not yet fully recovered from injury and was putting on lack luster performances week in and week out, yet still held on to the title ^.
Don't forget Unforgivine 2002, Rob Van Dam....
Also even worse, not just a dirtsheet one, SummerSlam 2003 and injured Triple H who can barely walk still reclaims the title for the sake of it. I know he lost the next month, but that didn't help Goldberg.
Also Wrestlemania 2003, against Booker T.
All of that ^, that's a few reasons to complain.