the main issues with iOS 6.1 are for two reasons.
One is scot frontal, who is the reason we have siri and terrible maps and other gimmicks that really weren't needed.. he was in charge of all iOS software before tim cook took charge, now the reason iOS 6.1 has some issues is A iOS 6 had some major hardships when it comes to bugs and so on for 3rd party apps as far as Im aware, this meant that some features didn't work as they were supposed to, also the iPhone would get confused when it was on 3g and try connecting to any wifi it could, causing slow browsing and battery drain.
apple wanted to get scott out of the picture super fast as he haas lead iOS down a rather strange route, bringing lots of half finished or broken features to the iOS market. so 6.1 was a major update as far as they were concerned, they wanted to move on, however they may have developed a bit too quickly, but as a developer I can say there were 5 beta stages for this update before it was released, and that is more than the usual 3 or 4, showing apple wanted to get it right.
so to conclude, they had a bad start point that cant be fixed or changed in 6 months, they also needed to fix a large number of bugs quickly and siftly for iOS 6.
but dont worry about apple going downhill just yet, its early days of tim cooks plan to make the company better, last year they became a mobile device company which means that they are now focused on iOS.
also John Ive is now in charge of the iOS devices and iOS itself, so wait for iOS 7, this will have the features and design we want from such a beautiful product, also john has a much better quality level, as we can see from his design progressions from iPhone 3g to iPhone 5, so let them fix the bugs and hold tight, things will change and only for the better.
thats my opinion on this, and the only reason apple gets slated for some tiny and some rather large bugs is because they have had such a long record of there stuff working flawlessly or with very little incident, and now a couple of mistakes have been made they seem to get the heat...
but people don't have a go at Microsoft for there stuff ups anywhere near as much...