While all these are valid points, you just have to compare hand- and machine-washed glasses once and will never confuse them again. I believe that standard machine cycle includes enough rinsing to wash off detergent, but you may do another rinse just in case.
If I want squeaky-clean glasses, I clean them by hand so I can't say that I relate to your experience. Perhaps the dishwashing detergent that you use contains different chemicals.
Might also be because people misuse the dishwasher a lot - by overloading the machine past capacity, and then running an underpowered (or "eco") program. All those other programs are on the dishwasher for a reason, and it's not to trick the user into wasting more water.
