WHAT PART OF LISTENING IS STILL DIFFICULT?

I think that I still find it very difficult to understand the different pronunciations of people, as there is English and British American so it is more difficult to understand, I also believe that fluency and coherence is important to understand the message you want to convey. For example in some videos I understand a lot of what people talk but in others that it makes me very difficult to understand and with some teachers happens the same and the reason is the pronunciation that they handle when it comes to speaking the English language