"In other words, we are never strongly addicted to things we can consume at high frequency, but rather to things we can never get enough of — particularly when we can’t figure out the exact pattern of when to reliably expect them. A craving, in this sense, is a negative surprisal episode triggered by a prediction error. The more unpredictable the pattern, the stronger the craving!"

https://www.psychologytoday.com/blog/culture-mind-and-brain/201610/addicted-your-phone-science-has-good-news