Supply centers are what constitutes the core of sustain. For the price of 400 resources, you get to have production of 155 resources per minute. What this means is, you invest in your long-term future, pay 400 resources now so you can have more than that in roughly 2.5 minutes. This sounds like a sweet deal, because it is, but if you are in dire straits and you need resources for producing units within 1 minute (for incoming attack) then you might consider going for a short-term solution because it may be your survival that is at stake.
Whatever the case is, eventually: Supply Center is the center of your universe and is to be defended as such.
AoW3 Confederate Supply Center upgrade priority:
- Automated Storage
- Resource Planning System
- Hardened Ceramic Armor
- Building Construction
A Supply Center provides resources. Due to logistical problems, every next Supply Center on the battlefield provides fewer resources than the previous one.