If I try to edit text I have typed out, it is very difficult. It’s impossible to place the caret in the middle of a word and difficult to place it between. Very frustrating and I don’t understand why.
I have always struggled with this too. My best guess is that it’s just hard for your phone’s touch screen to tell exactly where you are pointing. I’m not a smartphone touchscreen expert but I know that they are not always very precise, which is why for example your on-screen keyboard uses predictive software to improve the experience (with autocorrect as a backup).