Tannic helps in aging.

[Innkeeper]

Hi Junifer, and welcome to the Wine Board. It is not so much that the tannin helps in aging, as it is that ageable reds almost always have high, hard tannin to begin with. It the wine has sufficient fruit, acid, and other elements they will tame the tannin over time (smooth it out) as well as morphing the entire wine into a wonderful new experiance.