If your meat comes off the grill tasting burnt and ashy, you might've cooked the steak over too much flame. There are a few potential reasons for this.

When your grill flares up, a lot of soot is released. This plume of soot and ash can shoot directly at your food, coating it with a thin layer of carbon and fuel residue.

Fat dripping onto the hot briquettes of a charcoal grill can cause flare-ups, and fat can also cause gas or propane-fueled burners to flare.

Faulty burners can also cause the fire to spark higher than it should, as can a bad regulator. If these issues arise, shut off the grill and check on it before continuing to use it.