Auto-Correction learns from your input/actions (what you enter, which words you often use, which words you don't use), that's why it's getting better when you use it.I Was wondering if Apple also updates Autocorrect with it's new versions of IOS even of they don't usually mention it ? I noticed that it seems to become more effective lately and is able to recognize words so better results.
It’s also possible, even likely, that they have improved things on the back end. Apple does not mention every little tweak they make wiht an iOS update. If they did it would probably be several pages of dense type.