Lol, I'm just experienced
Most people don't take long enough draws to activate the cutoff. I mostly know about it because my first ripoff kit had like a 3-5 sec. cutoff and it drove me insane!!!! Probably why it didn't stick the first time around. It was an auto and I had to puff, stop, puff again just to get one good hit. I take long draws anyway, but that was EXTREMELY frustrating I was SO happy to have found Vapor4Life and their wonderful hardware The difference is night and day!