Shampoo is nice. You put it in, lather, massage your scalp, and then rinse. A nice in and out procedure.
Conditioner is different. You put it in, and then spend the best part of the next ten minutes trying to get it off your hands, and wherever else you might have wiped it in an attempt to get it off your hands. And you can never get it out of your hair.
When people do the exact same thing, we refer to them as "house-guests who overstay their welcome." Things are fine at first, but after a few days, you're pretty much sick of their continued presence. You are reduced to dropping subtle hints (i.e. "I think I'll be driving past the railroad station later today, is there anything you need?"). But in the end, HGWOTWs can be easily convinced to leave by a mere phone call to the local police. This technique fails dismally when applied to hair care. The last time I called 911 to complain about conditioner, the dispatcher kept asking to talk to the adult in the house. I gave up.
I understand that experts in the field of hair maintenance will tell me that the persistence of the product is merely it doing its job, not unlike the burn that results from the application of alcohol to a wound. But I think this is something chemists need to be working on: a substance that makes your hair smooth and velvety without rendering you convinced that you still have product residue in it. It will allow people to step out of the shower feeling clean as the day they were born (absent all the blood and membrane and that damn annoying umbilical cord), which is what a shower is, at a fundamental level, supposed to be about.
Now it is possible, that at 1:29 A.M., having studied Evidence for most of the past nine hours, I am not looking at this conditioner problem clearly. Some may say my senses have been clouded by excessive exposure to yellow highlighter fumes. Others may argue that there are other more important things to complain about, such as world poverty, excessive militarization, and global warming. But you gotta' start somewhere. Who knows? Maybe someday I'll be able to move on to the problem known to most as "handsoap-that-leaves-dried-scum-in-the-soapdish." But such grandiose aspirations will have to wait for a later day.
I urge you to visit
https://rn.ftc.gov/pls/dod/wsolcq$.startup?Z_ORG_CODE= if you wish to lodge a complaint against the conditioner industry. Only through concerted action can we prevail on this issue of universal magnitude.