Why the Terran vehicle crewers look 'unprofessional' in Starcraft II. (Lore explaination)

If you ever looked at the portraits of the Factory units in Starcraft II, they tend to look less ‘military’ and more ‘unprofessional’ from Starcraft/Brood War to Starcraft II (e.g the Siege Tank driver in SCII looks a lot like a mechanic) . For the Raiders, they are disgruntled civilians that were recruited by them who have previous experience with operating vehicles and hence became vehicle crewmen. But what about the Dominion ? Well, for the Dominion, there are two fates for every criminal sentenced to neural resoc, becoming a marine or becoming a vehicle crewer with new skills to operate the vehicles in the Terran Dominion’s military granted to them by the neural resocialization process.

(This can be used to explain the Hellion/Hellbat, Cyclone and Thor pilots in the unit portraits, they were originally criminals who were sentenced to serve as vehicle crewers. )

I mean, the vulture from BW doesn’t look very professional lol.

Yeah though, this is the entire terran army lore, they’re all criminals.

The logic behind this is that these personalities are more effective for committing into a battle. They have nothing else to lose because their human livelihoods were sunk in unlawful things. Therefore there is no fear in their lives. They have nothing at home; they are criminals because they made choices that sprang from not valuing those around them. If they value those around them, they would not hurt them. But they hurt them due to valuing something else more than people. They ended up as criminals because they hurt others.

Therefore, to make up for it, they are recruited to hurt aliens, so as to protect other people from dying to aliens.