if he had given up the prison, what's to stop the governor from doing it again? what's to stop anyone else from doing it again in the future? moving would entail new terrain, new risks, possibly new enemies, and more vulnerability in general. remember, we know who might and might not die...from the characters standpoint, they could die easily at almost any time.

they also had tons of food growing (you could see it in the shootout scenes), they were getting up enough supplies for the winter. they also had fresh water, something that is hard to come by. that's a hard thing to leave behind, especially with winter coming. scavenging is hard enough as it is, places are either picked clean or have zombies. imagine carrying say, a weeks worth of groceries in the zombie apocalypse. now amplify that by how many people are in your group...possibly dozens. the necessary supplies per day add up quick.

the prison also added more to security than the fences. there's thick concrete walls, secured windows, and with the steel doors of the cell blocks, there's layers of protection. first the two outer fences, then the inner fence, then the outside doors themselves, then the doors leading to the prison blocks, then the doors leading to the cells. doors by the way, that are designed to be sturdy. even if all the outer fences fell, walkers would never get through those doors. that would complicate getting in and out of the prison to resupply, but it would be safety nonetheless.

it would be pretty hard to find a place comparable to the prison, especially for soo many people. if they hadn't of been in the prison when everyone got sick, they might not of been able to quarantine them, or have it safe enough to treat them. the prison offered a LOT of breathing room.

they knew they could die when clearing and taking the prison, so when someone comes to take it from them, there's really no difference between defending your home from walkers or the living. both are on your doorstep, and both want to kill you. they've had to fight everyday to keep that prison, in some way shape or form.

 

TG wanted whatever Rick had period. He has been gunning for Rick. TG lied about everything to the people and tricked them and got them killed. Its all TG fault.

 

Who says the gov would have given H and Mich back even if Rick agreed to leave the prison? I'd reckon he'd have killed them both anyway.

 

I think Rick was looking to persuade The Governor to leave peacefully and let his hostages go, not for a big battle. "Fighting" wasn't the outcome he was hoping for.

 

If Rick is guilty of anything, it is not prepping and fortifying the prison in case of another attack from the gov or anyone else. No sniper rifles, no 50 cal, no ditches to stop/slow vehicles down. I'm not even sure that all falls on him but the council. It appears they didn't have a contingency plan (or a weak one) if anything would go wrong and evacuation was necessary. You think they would have learned from Hershel's farm and the first attack.

From Rick's standpoint, he thought the govenor was out of the picture. It was just another day in the prison and all of a sudden he is watching his friend and Michonne being held at hostages. He has to make an instant decision. Talk about pressure and having to think quick. It's easy to say he should have done this or that, but it would be overwhelming pressure. Rick knew he couldn't trust the governor but hoped to speak to the humanity of the others.

 

Its easy to look at this in retrospect. Also remember it was never RIck's choice. The Governor cut off Hershel's head quite suddenly, and of course there was going to be a battle after that

 

Q: 'What did Ricks group gain by fighting'
A: life

 

rick should've said let me go tell my people we have to leave, then had his best shooter find a good concealed spot from which to take out the gov. with the scoped deer rifle. with the gov. dead his group would've probably been in disarray and went back to woodbury or at least not immediately launched an all out attack.