Time is a valuable commodity for people. We are all finite on time and it is relative to our own lifespan. Every decision or action is a form of spending time.
By nature, people don't like to spend without gain and the constant spend of time is an inescapable part of life. Every second is time spent but satisfaction of spending comes from the value derived from events, manifestation of skills or other notable achievements that a person realises.
If you are thinking about spending, perhaps self reflection on how we spend our time will be a great place to start.