In this case, it is the basic idea that if you don’t use something, you will lose it.
One of my current tubes of toothpaste was running out, so it was time to tap into the Museum to find a new one. I pulled out one of my very favorites — Trybol. Unfortunately, Colorado’s dry climate had taken its toll — the paste was rather hard. (But it is still usable.) If I had pulled it out a few years ago, it would have been perfect. Alas, I waited too long.
Moral? Use what you have. Now. For the purpose it was intended.