In the Academy, Sentinel learned that the only person he could trust was himself. No one had meant for him to learn that, just like no one had meant for Elita to die. But he learned it just the same, and she died just the same.

He was the only person he could trust not to get people killed, not to lose people, not to abandon people. Everyone else either was incompetent or cowardly, no matter what they seemed to be like on the surface.

His time as a Minor reinforced and added to his belief. One of his own recruits turned out to be a Decepticon spy. He couldn't even trust people not to be working for the enemy.

Somewhere along the line, he met Jazz. Jazz was... strange.

Sentinel kept expecting him to fail somehow, but the cyber-ninja never did. It worried Sentinel; if he didn't know how Jazz would let him down, he couldn't plan how to handle situations where he had to work with Jazz.

Jazz was infuriatingly capable.

He didn't really notice when he stopped worried about Jazz failing on him. It just happened. Jazz would be there where he was needed to be, and Jazz would back Sentinel up, and Jazz was everything Optimus was supposed to have been, only better.