I was going to post exactly this before realizing that someone else undoubtedly posted it before me, and I should upvote them.
I will only clean my charcoal grill with some hotter fire and a good whack from the grill spatula. Excess [0] ashes go into a bucket for later non-cooking uses. The carbonized residues on the grill create an ablative non-stick coating for any foods you put on it. Also, they make your grill marks black, when they might otherwise be red from the rust.
[0] Excess being defined as so much that the charcoal won't light.
I will only clean my charcoal grill with some hotter fire and a good whack from the grill spatula. Excess [0] ashes go into a bucket for later non-cooking uses. The carbonized residues on the grill create an ablative non-stick coating for any foods you put on it. Also, they make your grill marks black, when they might otherwise be red from the rust.
[0] Excess being defined as so much that the charcoal won't light.