L wants to treat every encounter as our last.

In training, we learned that we need to treat every encounter with a witness as our last. This is because once someone knows you're looking for them, they disappear. They ignore your calls, refuse to answer the doorbell, and even change their habits so you will never see them again. 

That's why it's crucial to make your first, and last, encounter count. We usually subpoena the witness and try to get any information we can during that time. We go through each second of the encounter trying to make it last a second longer. 

I've wondered what it would be like if we lived our lives with the same vigor. What if we treated every encounter with a stranger, friend, loved one or family member as our last? What if we just said everything we've ever wanted to say today, not for some phantom tomorrow? What if we didn't take our mundane encounters for granted, and instead acknowledged them as happy collisions of fate and humanity?