Maintenance's self service is not taking effect every battle like it should.
Both myself, an alt of mine and annother player experienced Maintenence's self service not working.
I tested it myself and it worked fine, so if it isn't working for you and this other player, you need to pony up more details. What weapons you're using, what rank are your maintenance talents, what do you define as 'not working', what durability/max durability they have, things like that.
Maintenance is lowering a weapon's durability to its maximum repair value. A weapon with 40/40 durability will suddenly have 30/40 durability after the battle ends, assuming a maintenance cap of 75%, even if the weapon went completely unused during that battle.
It -used- to do that, before I fixed Khalid's bug, but it shouldn't be anymore.