Is it necessary to wash a shoe shine buffing cloth or do you just keep using it?

Had to shine boots every night for years. Once you have the technique down all you need is an applicator brush, a buffing brush, an old t-shirt, and a few drops of water. Oh, edge dressing and a toothbrush to hit the sides of the sole. Just throw out the t-shirt when completely used.

I have my manservant use a fresh one for each polish