All hair has three stages in its
growth cycle: anagen, which is the growth phase, catagen, which is the transitional phase, and telogen, which is the sleeping phase. Each step lasts a different amount of time, but on average, the growth phase for eyebrows lasts between 30 and 45 days.
People of different ages have different biological factors that affect when their eyelashes stop growing. The normal cycle of hair growth also plays a role. In general, eyelash growth slows down with age, just like hair on the head. But eyebrows usually keep growing even when you're an adult, though not as quickly as they did when you were younger.
There is no set age at which eyelashes stop growing all the way. Instead, things like genes, general health, changes in hormones, and living choices can affect how long and how well eyelashes grow over time. Eyelashes can still grow in older people, though they may do so more slowly than when they were younger.