A person can spend years preparing for an event that lasts less than the introduction.

Preparation and event are almost never proportional. Years of work can be spent on something that occupies a few minutes, and the mismatch feels absurd from the outside and often from the inside too. But the years were not a down payment on the minutes. They were where most of the actual living happened, and the brief event is simply the visible edge of it.

If you are deep in a long preparation, try not to store all the meaning at the far end. Look for what the work itself is giving you now. And when the event passes quickly and leaves you strangely flat, that is common and not a sign the years were wasted.