For real Go beginners counting is not of relevance during the game… it is done at the end of the game to determine the score.
Progressing to higher kyu ranks “counting territories” becomes a relevant skill during the middle game (in Japanse: chūban) for developing a well balanced style and for estimating the score. Counting becomes part of other essential methods, e.g. “positional judgement“.
… shortly before Xmas a lecture on GoKGS was given by Shawn Ray (4Dan and known as Clossius) who is studying Baduk (Go) in Korea.