10 years is a long time. That's a whole decade we usually only get about 10 of those decades to live.
10 decades is 100 years. But I agree 10 years does go by pretty fast. When I was 10 it seem 10 years was forever and getting from 10 years to 20 years old seemed to take forever but now that I'm past 20 the 10 years seemed to have gone by really fast.
Time seems to speed up the older we get.