Why are the intervals between laser hair removal sessions shorter in the initial sessions and longer in subsequent sessions?

Hair on our bodies exists in three different phases: anagen (growth), catagen (regression), and telogen (resting). Laser hair removal can only remove hairs in the growth (anagen) phase. In the first sessions, because the number of active hairs is very high, the intervals between sessions are shorter, such as 4-6 weeks, to target the hairs that have recently entered the anagen phase. As the sessions progress, the number of live hair follicles decreases, and the growth rate of the remaining hairs slows down and their cycles lengthen. Therefore, the intervals between sessions are extended to 8-12 weeks to allow time for the amount of hair that will emerge above the skin.