For me, it's because the people I've called my request in to don't even put the request in. Not even if you go in person!
Because the maintenance people that do come are too lazy to actually fix anything. My air conditioning was out for two months last summer because the "maintenance person" (if you could even call him that) was too lazy to even see what the problem was. After pitching a holy fit finally 2 months later a maintenance person who actually does work fixed it in less than 15 minutes.
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