Chapter 4 addresses the question of when certain events of TD have to take place for a viable line of the pursuit of excellence. ECT views the life cycle of a person as significantly constraining the timing of developmental events and processes for achieving any long-term goals. When human excellence is concerned, social conventions and cultural provisions further constrain what should be done and when it needs to be done. In other words, developmental corridors can be opened and closed at specific developmental junctures, prompting individuals to pick the best timing for engagement in specific endeavors that might have a better chance of success. Based on research evidence, ECT postulated two main concepts: developmental windows, which vary from domain to domain, closing certain developmental corridors (e.g., to become a musician) but opening others (e.g., to become a biologist) for the exploratory stage, and developmental progressions, which stipulate a temporal sequence of milestone events and critical transitions that have to take place to sustain TD. Finally, distinct Matthew effects, the cumulative advantage prevalent in TD, are explained over this TD course in terms of accelerated development as well as individual strengths, social recognition, and privileged access to opportunities and resources.