Clark only fails horribly if he proves he has no idea how to hire a GM with his next hire.
He went out and got the most highly praised candidate he could find for his first shot. I don't blame him. In hindsight it was horrible but it was kind of like drafting JaMarcus Russell. A lot of teams would have done it.
Alex Smith's current 9.8 YPC is one of the lowest marks in the NFL over the last 10 seasons. Only a few QBs have been worse:
Ryan Mallett (9.8), Derek Carr (9.4), Christian Ponder (9.8), Brady Quinn (9.8), Ryan Fitzpatrick (8.6), Brodie Croyle (9.7), Charlie Frye (9.7), Bruce Gradkowski (9.4), David Carr (9.2)