Knowledge regarding triggers for hairloss is of great importance. Testosterone and dihydrotestosterone levels go hand-in-hand. This is proven by those wanting to build more muscle mass or females wishing to be males who introduce testosterone augmenting substances into their systems. By doing this they also dramatically increase their chances at developing baldness. This has all been logical to us for a long time.
We've also seen men grow a lot of hair back in their attempt to transition to the opposite sex. Accomplished through drastically increasing estrogen, thus suppressing testosterone.
So again, with just this information at hand, we should actually expect an aging man to halt or even reverse his baldness. This due to testosterone declining with age. Yet the opposite is truth. Almost every man develops baldness to some degree as they age.
Indeed, there must be other factors at play that explain why even old men bald.
Dermarolling, brushing your scalp, applying liquids, etc. are agents utilized to provoke growth through stimulating circulation and wound healing mechanisms. As most will testify, improvement of ones hair will vanish promptly after these routines are eliminated from their schedule. A reasonable explanation for this is that they only raised the ability to grow hair. The culprit was still there.
Sadly, the system is too concerned on relieving symptoms rather than digging down to the roots.