For some people, the highest THC is some sort of goal. My understanding is that this is scrapped off the insides of the tubes used to produce BHO. The flip side is the people that understand that a lot of the other compounds (terpenes, CBD, etc) significantly add to medicating effects in different ways, and as such, they are doing "live extracts" and adding extracted terpenes back into the mix. Personally, I don't need that kind of concentration of medicants, but I understand that there are those with tolerances high enough to warrant those things.