Chris Grier joined the Miami Dolphins in 2000. He was a member of the scouting department. In 2003, Grier moved from an area scout to a national scout and also served several years as the Assistant Director of Scouting.
In 2007, Grier took over the director's role until 2016 when he became the general manager. We don't know the interior influence that Grier had on the team as a scout but he had his hand in decisions or at least helped to influence them as the Director of Scouting. His real influence came when he took it all on his shoulders.
Grier has done a few things well. He has a great capacity for dealing with other teams and he doesn't get railroaded by more experienced G.M.s. Grier knows the value of the trade market and identifies good value. He has a good reputation with owner Stephen Ross as well.
The biggest issue is that Grier has also failed consistently in areas that would get most general managers fired after a few seasons. The relationship he has with Ross and the fact that Miami has three consecutive "winning" records, is enough to keep him around but at some point, Ross needs to hold him more accountable.
Yes, the NFL is a tough place to win and yes the AFC East is a tough division that watched the Patriots slip and the Bills ascend. The Dolphins have remained the bridesmaid.
Grier made one of the biggest blockbuster trades in NFL history when he sent Laremy Tunsil to the Texans. That trade ended up bringing the Dolphins, in one way or another, Tyreek Hill, Erik Ezukanma, Solomon, Kindley, Jaylen Waddle, Jevon Holland, Noah Igbinoghene, and Channing Tindall.
Of those, Holland, Hill, and Waddle have made the only real impact on the roster. This is from a pool of draft picks that included 2 first round selections and a second round selection. Grier was able to move some of the selections to gain more draft picks.
This is what Grier does well. This is why fans still believe he can get the job done. The problem is Grier doesn't hit with his draft picks and that is a big problem.