Usually, it’s a lot easier to grasp the cost of an action than that of inaction.
It costs $X to service your car. But what does it cost to not have it serviced?
It costs $X to buy that book and Y hours to read it. But what does it cost to not know what you’ve learnt from reading it?
It costs $X, a phone call, and one evening of your time to invite a friend you haven’t met in a long time for dinner in that new restaurant. But what does it cost to not spend the evening with them?
It costs $X to book a coaching session plus an hour of preparation, three hours to meet, and the guts to implement the insights. But what does it cost to not book it?