Postal deliveries have been getting later and less frequent basically because THEY dont want to pay for sorting to start early. My local sorting office used to be a hive of activity from about 4:30AM, nowadays they dont get in the building before 7:00AM, and there are much much fewer of them. Much sorting is done in remote centralised sorting offices by people who don't know the area.
It is vastly annoying when a letter or parcel gets mis delivered, it happened way back then, and probably moreso now, but semi-literate posties are not the only cause. Look out for postcodes with letters and numerals transposed, look for semi legible addresses. Look for town planners who planned estates with interleaving streets all with similar names. Look for houses that cannot be identified because the number is the same colour as the door.
Knowing something of the scale of the operation and its history, the investment in the last 50 years would have bought Andorra and a large part of some of the smaller states. The technical changes in that time have been enormous, the phrase "postal mechanisation" covers a mountain of effort and money, but mechanisation can never really replace doing it by hand when much of the stuff is hand generated in the first place.
For those who say that it needs privatising - go to, say, DHL, and ask them to take over. If they had to create their own infrastructure, you wouldn't see their heels for dust. If they took over the existing infrastructure, they would demand a subsidy that would make anybody's eyes water. At the moment, in some circumstances, the private mail delivery companies, those who handle bulk mail, use the postal service to actually deliver the stuff to individual destinations. Gradually building up a parcel handling service, starting as and where it is convenient and expanding as when it is convenient is one thing, providing a universal service, even one as patchy as the postal service has become, is a different ball game altogether, and just isn't going to happen.
The big difference between the previously privatised services and the postal service is that the previous ones have all been some form of pipeline that involved some physical input and a lot of accountancy. Basically you are just picking whose accounts department gives the best deal. Delivering mail, however, involves actually having people going out and delivering.
And it doesn't matter who you vote for. The government still gets in, and things still go downhill.