I wonder if this isn't tied to the time of year. Not that it's not an issue all year, but the end of the summer season marks the end of the longest "busy" period of the year. For basically three straight months, the crowds are thick, there's very little scheduled "down time" for attractions to do maintenance, park hours are longer (the night shift is shorter), resorts are full... I think it's just harder for them to keep up with everything that needs to be done. I think maintenance probably suffers the most in August than any other time of year because of this.
I know for some people this is the only time they can go (August is probably the best time to go for teachers, for example), but you'll probably find better temperatures, better maintenance, and less "crowd" mess (overflowing garbage, etc) during Oct/Nov/Jan/Feb.
The overflowing garbage thing sucks, but at times, it's almost inevitable. With more and more people drinking bottled water/drinks (instead of reusing/refilling them or taking drinks from water fountains), the trash bins are going to fill up during the crowded times. And instead of holding on to their trash for a bit until they find an empty bin, they just try to cram it into a full one, or worse, just toss it on the ground. People just aren't as respectful as they used to be, which also ties in with the chipped paint, gum being stuck on things, etc.
Also, with modern technology and computer integration in attractions these days, safety systems are incredibly touchy. Back in the day, an attraction wouldn't be shut down due to a faulty sensor or a strict computer safety routine; they didn't have them. It can take time to go through the safety checks to get an attraction running again after that kind of shut down.
And sometimes, it's streaky bad luck - wrong time, wrong place.
Yep, PP down for 5 hrs. Splash down all day on Tuesday. Very frustrating. Also, on Tuesday at MK, food places shutting down hours before park closing. Columbia Harbour House closed at 5:30pm?!?! Why? Many booths with popcorn, ice cream, etc closing down around 7pm. Really, really annoying.
I'll say that I've experienced this same thing at DLR. Food stands (popcorn, lemonade, churros) and restaurants closing well before park close.
Harbour House closing at 5:30 isn't the norm, but it does close early sometimes. It seems like it's usually open late (9PM or so). The WDW website posts the hours. (ETA: Just checked, here are the closing times for the next few days: 29th - 9PM; 30th - 5PM; 31st - 9PM; 1st - 9PM; 2nd - 9PM; 3rd - 5PM)