Hair has a natural cycle of growth. Starting with an empty hair follicle the hair develops from the bulb at the bottom and grows starting with a very thin soft fine tip. This makes the hair soft to the touch. As the hair grows it becomes longer and thicker. Eventually the hair falls out of the follicle and it remains empty for a period of time. The cycle is then repeated.
It is necessary to shave the hair before laser hair removal. The aim is to have fine stubble so that we can treat the approprate area. If you shave the hair you cut the shaft across the thicker part near the skin, and as it grows you have a wide flat tip of hair with no fine taper. This then feels course and brittle and it is no wonder that people think that hair growth is now worse. As the hair grows these bristles get longer. This is not permanent.
This is only temporary, and if nothing else is done then the hair will fall out in time and a new soft tipped hair will replace it.