This is more a thought and possibly even a question to those who know more than me about the Flow concept. I have spoken about Flow in the past and use it as a core principle to engaging long term design.
However, recently it occurred to me that long term exposure to extremes in frustration or boredom, could alter our perception of flow.
For instance, you spend months in the boredom phase. You have little to no challenge. It seems reasonable that you would need to boost the level of challenge to help improve engagement and in turn try and get closer to this idea of flow. Below is the “ideal” mix of skill and challenge as described in flow theory – only this time plotted against time.