@JoeBobMack
"I hadn't thought about that," Abby said.
"It could make the transition more difficult," Carol said.
Jim nodded and added, "Not to mention the expense."
I determine if WHO said something is more important. Or if WHAT is said is more important at that moment in the story. This applies in my stories if it is a couple of friends relaxing, a meeting in a staff room, a group herding cattle, or soldiers in the midst of combat.
If WHO is most important, then I start the sentence/paragraph with the character:
Seargent Major Smith said, "NCO Meeting in my office in ten minutes. Fall Out."
Staff Sergeant Johnson said, "No can do Sergeant Major. Captain Klink ordered every swinging Richard in Alpha Company must be present for remedial PT in fifteen minutes. We had ten men fall out during the morning run."
"What a goat rope!" Someone in the rear ranks muttered loud enough to be heard.
I think it is important that the Reader knows who is saying the dialog. When it's just two characters you don't always need the character's name first, it may be presumed (and confirmed at the end of the sentence or paragraph). With multiple characters it is usually better to identify the character before they speak. However, sometimes for impact/story reasons, such as someone interrupting, or an Exclamation, I may choose to ID the character after what they said.
In high stress situations, such as combat, I am more prone to having dialog first, and character second, occasionally unidentified to the Reader (I will maintain notes telling me Who said something, so I know what is going on. I may not care if the reader completely understands, or may intend them to be confused in the chaos of combat. I still need to know what is going on.)
An example (slightly altered for simplicity) from my story:
Sergeant Major Hernandez was hit, and slumped over. Corporal Cruz grabbed him, and shoved him towards Jimenez to treat his wounds; Cruz charged the machinegun and began firing.
Colonel Diaz yelled, "We are being overrun on the left! Sergeant Major Hernandez you must keep firing until A Company gets here!"
As the enemy kept coming despite the machinegun fire, Colonel Diaz spoke into the radio, ordering, "Captain Ruiz you must bring up A Company immediately! We are being overrun!"
"Sir! General Obrador is demanding a situation report!" Sergeant Maldanado shouted.
Colonel Diaz grabbed Lieutenant Fernandez by the shoulder, pointed at the low stone wall, and said, "Get your men over there and Hold at All Costs or we are Dead!"
"Sir! Sir! General Obrador is insisting--"
A round impacted the command vehicle between the distraught sergeant and Colonel Diaz, who shouted, "I am leading my Battalion, I have no time for that fat Pendejo!"
As he moved out of the field of fire, Colonel Diaz saw an enemy dart from behind one of the stalled trucks, and shot the foe with his M-4; Diaz shouted, "Sergeant Major direct your fire to Six-o-clock, we are being flanked!"
As he stepped back seeking cover, Colonel Diaz noticed the Sergeant Major laying on the ground, being treated by a medic; Diaz said, "Who the hell is on the gun?"
"I am!" called Corporal Cruz.
IMHO the more characters in a scene, Main and Secondary characters should be identified before they speak. As should a character, if it is useful to know Who they are before they something. In my combat example, if he was going to say something "Medical" I would ID the Medic first, as it would seem odd being said by an infantry soldier.
If it is Information I want the Reader to know, but it's just a 'spear carrier' I would likely have the dialog first: "They're breaking through on our right too!" said Xyz. Or if I want a feeling of chaos I might have the name after, or not at all.
Try to view it from the perspective of your Reader.