Title says it all. If i smoke 0.5 grams, im pretty stoned, but when i smoke 1 gram i dont feel any higher then i was when i smoked .5 grams.
Because of drug tolerance. Drug tolerance - Wikipedia If one first smokes 0.5 gram followed by several weeks of not consuming any THC and then during a second day smokes 1.0 gram, one will indeed get higher during the second session. However if one smokes likewise with a short period between sessions, one's neurotransmitter and many other bloodstream chemicals will have gone out of normal balance including available CB1 receptor sites onto which THC binds in order to cause high effects. My own experience over decades is it takes me about 5 days of a tolerance break after just smoking a single time that was itself preceded by several days of not smoking, in order to not experience noticeably reduced highs. If I say smoke a gram of high potency THC flower at noon after a week long t-break, that would give me a super high from 1pm to 3pm. It doesn't matter how much or how strong of THC I smoke later that day at say 6pm, as I won't come anywhere close to what I felt earlier as my body chemical levels have already changed and available CB1 binding sites decreased limiting what is possible. That is why someone that smokes daily cannot get as good a fresh clean high as someone coming off a longer tolerance break regardless of how much they dab.