This question already has an answer here:
- Why is the Night King so slow? 6 answers
From the starting of the season.In season 1 episode 1 to the season 7 episode 6 we can clearly view that white walkers or army of dead can run fast and also can catch a running man with maximum speed (maximum speed here means a man running for his life). We can see them running or walking fast in the second last episode of season 7. So why they were so slow. This is a plot hole or there is some theory behind it?
Edit: This is not a duplicate question, that question which you are referring is not answering my question. My question is simple that why they are being shown at slow pace. Secondly in the duplicate question how people can speculate that this is a war strategy. There is no such thing in white walkers like war strategy ever mentioned in the season.