I'm saying that he wasn't handed an offensive line with three 1st team All-Pros in Detroit. He didn't have the league's leading rusher standing behind him. He didn't start out in Detroit with a future HOF TE and Pro Bowl WR.
As a rookie with the Rams, they put him in after the team had already started out 4-5. His defense allowed over 30 points in the first four games he started. Gurley averaged 3.2 yards a carry for the 7 games Goff started.
Three years after joining the Rams, they are in the Super Bowl. Three years after joining the Lions, of all teams, they are in the NFC championship game. Look at where he started in both cases. Look where he ended up. Coincidence?