None of the stuff sold as "ecstasy" or MDMA in most parts, is brown, it literally looks like sweet tarts and people were iffy about it back when that was how so much of it was sold.
Then, because people are stupid, I'm not sure, the stuff got replaced by "Molly" or "MDMA" which came in powders and pills that were clear. Basically, the quality of the presentation dropped, the ability to tell whose stuff was whose dropped, and yet I knew people who swore up and down the quality of the stuff had risen. My girlfriend used to hang out with people that dumb and falling for this kind of stupid crap is what became the last straw.
It was about 5 years ago at least, when a few labs let people send stuff in and get it tested no questions asked. A lot of the stuff sent in, didn't test as what it was supposed to be. It doesn't help that so many drug dealers, if they were allowed to speak without consequences, admitted they put things as sketchy as hairspray in things as basic as Weed.
Basically what it comes down to, is that people want to experience a lifechanging experience and somehow have it cost as low as 15 dollars or something.
It's like a 500 dollar brand new Kalash made in the US (Even 5-10 years ago prices), of course it's going to suck.