What is this post based on? Why would AD systems be storer in warehouses? Is it not their job to be on 24x7 and keep a vigil?
During war or during crisis yes, AD system operate 24x7. During Peace time not so much.
It cost money to operate such system 24x7 and no country is ready to waste resources when not needed.
Second, this systems have optional life just like aircraft. One doesn't wants to waste their operational life.
By storing in warehouse means that these units are located with their unit's peace time location. And yes sometimes it means that these assets are stored in large warehouse labeled technical ares in the military base.
As far source, its known SoP. During peace time (alter status) only civilian radar, long range search radars and radars near critical installations are operational. Sophisticated AD network are only used/primed during training and maintenance.