It's an indication of quality and standard control.
If you get one today and it taste, feels, burns and smells one way and differently some other times.
I'm probably not staying with the brand no matter how good it was that one time.
Discussion
As yuu can see on my "pictures" I also tried a lot of brands. Unfortunately one brand was ripped out from my installation. Somebody took the Cohiba Behike tube. 🫤 So I had to replace it with a cheap Vegafina ☹️