Let's stipulate there's a racer out there who feels tired. He blames it on his work. But when he changes his job, he's still tired. He goes to a doctor. The doctor comes up with a diagnosis and prescribes a drug regimen. The racer does the regimen. After a while is feeing better. "Normal" even.
Only the drug is testosterone, a banned drug in all Olympic sports. He decides to app
Problems With This Testosterone TUE

You know, the worst part is that USADA doesn't care about the health of individuals. So what do they want Jeff Hammond to do? Have his doctor take him off of the medication to watch his testosterone fall and not only feel sick, but possibly began to experience medical fallout from the cascade of events of a failure of a portion of the endocrine system? When it was discovered I had low testosterone, I had to wait 6 weeks to get an endocrinologist appointment. My endocrinologist ordered a repeat testosterone, along with LH and FSH (pre-sex hormones) and my testosterone had fallen even further. He was so taken aback by the plunging of my testosterone in that 6 week period that I was sent for a brain MRI to make sure I didn't have a pituitary tumor. Luckily, I didn't but the end diagnosis- primary hypogonadism. I had the proper amounts of LH and FSH, but my family jewels were not taking that message from the LH and FSH to produce testosterone. I don't know how USADA to find it in the standard of medical practice to make a doctor STOP a medication that is proving itself to treat the condition, just for the sake of "having more proof" that the TUE is justified.
In other sports where there are a lot of TUEs for Testosterone, the biggest guess for why athletes have low testosterone is because previously using testosterone illegally they overdid their cycles and consequently their testosterone production never recovered.