Not everyone here says that it takes multiple treatments to kill a hair… Michael and Josefa are pretty big advocates for the “kill it in one shot” ideology.
Electrologists that say that you can’t kill a hair in one shot either don’t know any better (schools teach lots of misinformation) or are trying to simplify the idea of growth cycles because a lot of clients can’t wrap their head around the fact that there are dormant hairs that will continue to come in, especially in the early stages of having work done.
Simple fact is, if you destroy all of the cells that make the hair grow, that hair is dead. If you destroy the stem cells that can turn into those cells, the follicle is totally dead. If any of those cells live, that hair has the chance to come back - maybe weaker, but eventually, it will probably turn into a full blown terminal hair again.
Thicker hair is more resilient for a couple of reasons - the hair gets in the way and insulates the cells from the heat portion of thermolysis or blend, the follicle is more developed and thus there are probably more cells to kill, and the follicle is deeper, with the terminus of the follicle, where the hair grows from, is separated further from the bulge where the stem cells live, requiring more energy or pulses of energy in both locations to properly destroy all of the cells.
A lot of electrologists that don’t know any better can successfully do this just out of sheer luck, but if you know to target both areas, your ability to kill the hair in a single session grows. For electrologists not destroying all of the cells, the hair can very well grow back, albeit initially weaker.
As far as going every week for 4 months and not seeing results goes, first, we have all of this dormant hair that is continuing to activate and start growing. If it takes 6-8 months for all of the hair you have to cycle on once, it’s going to take 3-4 months just to have HALF of your hair turn on, there’s still another half left. Second, we tend to be pretty harsh on ourselves and often magnify our own problems in our head - a lot of people I see have spent an entire lifetime trying everything they could think of to get rid of their hair, so they’re going to be impatient, magnify the current situation in their head to a worst case scenario, and then convince themselves that it’s not working even if it is, especially if it is somewhere as prominent as the face. Finally, not all of the hair is going to be killed in a single shot since nobody is perfect and we all try to work as reasonably fast as we can while still doing our best, so some of the hair coming in WILL be actual regrowth of undertreated hair.
At the end of the day, I’ll give you the same advice I give to everyone that walks through my door… don’t just settle for what I (or in your case, your current electrologist) am doing, try out other people and go to the best one… if that’s me, great, if not, that’s ok, I’m glad you find someone better. I tell every one of my clients what to expect and that, if I’m not doing a good enough job on any particular day, I want them to call me out on it. I don’t want anyone that just settles on me out of convenience/laziness and I don’t want to ever get to the point where I’m complacent in the work I do.