One day you were in charge of an attack over the rebels, you served the Empire, everything had to be perfect, or at least halfway, so that Vader could be pleased. You were at one of the meetings as one of his solider

“The rebels fled away. And what am I left with?" Vader asked one of the generals. He knew you did rather well, considering your loyalty to the Empire, as he was monitoring how you fighted. He was more annoyed at how other generals we're leading you and other stormtroopers.