The Wounded (TNG)

[FaxModem1]

It's also worth noting the relationship senior enlisted have with junior officers. Namely, while the wet-behind-the-ears officers are the ones who are supposed to be giving the orders, they are almost always bowing to their Senior NCOs for direction in what to do. It's why Bashir and O'Brien have the friendship they do.

It's likely that O'Brien had a field commission on the Phoenix, due to the heavy fighting they were experiencing defending colonists. And Captain Maxwell appreciated his input in technical matters. There's also the question of whether or not O'brien would even want to be a commissioned officer. Miles always gave off the attitude that he liked getting his hands dirty, and appreciated not having to do all the fancy dinners and filing reports that comes with being an officer. I can imagine he said, "No thanks" any time a superior officer asked him to go through OCS.

[Revolverman]

It's also worth noting the relationship senior enlisted have with junior officers. Namely, while the wet-behind-the-ears officers are the ones who are supposed to be giving the orders, they are almost always bowing to their Senior NCOs for direction in what to do. It's why Bashir and O'Brien have the friendship they do.

I wonder if thats it. The unofficial pecking order being codified so that high ranking NCOs officially are above low ranking officers. I mean, today if an Ensign on a US Navy ship tried to tell a MCPO what to do, he'd be thrown overboard, even though officially, the Ensign would outrank the MCPO.

[SuccubusYuri]

Starfleet tends to assign seniority over various jurisdictions. Like, we see bridge officers assuming command all the time, even though in a lot of cases in TNG, for example, Crusher outranks damn near everybody. And Nog definitely takes orders from the Chief in the latter seasons. So there's probably some sort of priority system where rank counts, but also there's this "operational hierarchy" where no officer would dare order O'Brien around on how to maintain the station save for Sisko, unless it probably interfered with THEIR sphere of influence.

[SuccubusYuri]

Also I would find it fitting if O'Brien resigned his commission and just enlisted when he realized "Oh shit, I'm gonna have to do this kind of stuff EVERY WEEK"

[J!!]

There's not much in the way of evidence for it, but I like to imagine O'Brien's role as transporter chief was really a head-of-department kind of deal - he's the boss of all the transporter operators and transporter techs on the ship, makes sure they're trained and up to date, is responsible (under Geordi) for all transporter hardware, is in routine contact with the Daystrom Institute and wherever else is doing R&D on faster better ways to dismantle people and fling them across the void, oversees all the weird and wacky things they have to do to beam people and things around in ion storms and plasma whatevers and all that... It seems like all he does is stand in Transporter Room 3 moving the little light bars up and down because we follow the senior staff, and the senior staff get beamed by the chief personally, by the same token as when Riker sprains his ankle the CMO fixes it or when Picard spills Earl Grey on his desktop terminal Geordi takes the service call personally. In my mind the move to Ops Chief on DS9 wasn't so much a whole different kind of role - he already was head of an engineering crew - just a matter of his job on DS9 being all the systems, not just one of them. So by the same token, it could be seen as a move up to go from bridge officer on a small ship - an important role for that ship, sure, but there's one like him on every ship - to a department chief on the flagship.

THE ADVENTURES OF MILES O'BRIEN