When made correctly edibles will contain more drug compounds from the plant then you could get from smoking. This is, in my experience of making many edibles over the years, a major factor in the seemingly random effects. A given batch of weed will hit different when smoked vs eaten due to the different active cannabinoids in the edibles.

This really becomes an issue when weed has no real strict identity for it's cannabinoid contents. Indica and sativa is mostly based on vibes. The actual level of drug other than THC present in a given batch is basically unknowable and it's probable that some of that even varies within a given strain from plant to plant.

So even before you factor in the human elements like diet and metabolism, the edibles themselves are kind of a game of roulette on how it will hit you.

It's also incredibly easy to make them too strong. It took me over a year and tens of infusions before I had my edibles at a reasonable strength, and even then sometimes a different batch of weed would totally throw my recipes off. The time I made a batch with shake from several different strains was a real rollercoaster of being stoned.