We daily lose, on average, from 100 to 150 hairs and it's considered the norm. Before getting hair extensions you'd probably been finding your hair in the bath, on the floor and on your comb.
After applying hair extensions all these hairs remain inside of the capsule. If a master, while applying hair extensions, is taking about 20-40 hairs of yours, then after 2-3 months the capsule can be held up by only 10-15 hairs plus your lost hair. It puts a huge load on your hair roots and can affect the health of your hair.