What is the concept of microneedling?

[Monte]

I am seeking advice on how microneedling the scalp causes hair regrowth. I understand that by causing micro wounds to the scalp tissue, our bodies react by signalling more growth factors to the wounds. So far I haven't had any luck with microneedling and have tried multiple protocols. My hair loss is just getting worse and am paranoid that the microneedling has contributed to this. Until I have a conceptual understanding, I am reluctant to continue. So I have a few questions such as:

Treatment frequency???
Is the aim to wound the follicles before fibrosis occurs (which would clogs the pores) but only once inflammation has subsided (how long is that?), or fibrosis shouldn't occur with the right needle length and we can needle once a month or so to play it safe.

Needle length???
Are we looking to penetrate the entire epidermis layer or just enough to clean out the excess collagen/calcium. I know people have had great success using 1.5mm but also many haven't, maybe for some of us 1.5mm causes excessive inflammation and isn't required to just clean out the slight blockage at the top of the epidermis.

In my experience I tend to believe those like myself who still have a lot of their hair; don't require anything more than 0.5mm, as this may cause fibrosis and/or excess inflammation to surrounding follicles which contain hair. I think over time the excess collagen/calcification gets out of control and by then most hairs have fallen out, so 1.5mm is required. This is only speculation and would love to read about your opinions/experiences.

Thank you and much appreciated!