Why in the moment life feels stegnant but as we look back it's a whole new world?

I guess some people are really lucky that they are disciplined with life because of goals and ambition. like as years go by they also progress but some just continue fulfilling life duties and there comes a time where you look back and cannot realize so much of life has been gone and realize how much the world has changed. like how smartphone increased, remote work, social media, now it's rise of Ai.