It should be clarified whether this model considers entertainment activities as 'tasks.' If a person has high Impulsiveness, I intuitively see them doing a lot of things with high Expectancy, medium/low value, and little or no Delay. Example: videogames.

However, I do not predict that people with high Impulsiveness will sit around in bed all day actually doing nothing, so I think that the equation is flawed in that we usually understand Impulsiveness as a constant factor for a person, while Expectancy, Value, and Delay are all variable, depending on the activity being considered.