"not assertive enough".
It is amazing that airlines want certain characteristics in the cockpit during line ops, but once on the ground, and wishing to discuss certain matters with Ops management, your assertiveness can be a negative. Shut up, do as your told and don't interfer is a comon response. As a result line crews have no incentive to feedback and suggest. When I read the ideal charactieristics of pilot applications on airline application forms I am astounded at what they ask for.