You wouldent like coming into a terminating station on an nonairconditioned train sweating and seeing all those airconditioned rolling stock sitting there doing nothing (but I would prefer S sets over M's and A's)
You need to stop posting garbage. Just because the set is stabled there doesn't mean it's sitting around doing nothing. Stabled trains are often used for crew training, may be standby trains incase another train fails, may be waiting for a run to start, or may even be waiting to go to a shed to be exchanged with another set fresh out of maintenance.
Stop and think
for a second instead of spamming this and every other forum within reach.