Context is everything. I suspect that's why some home cooks are less conscientious about cleaning their grills - it's outside, everything is a little dirty outside! - than they are about, say, their ovens and stove tops.
But really, you should be treating your grill - especially the inside - as a sacred place and giving it the same care and attention you would any other major appliance.
"My feeling is that the grill grates should be immaculate and the rest of the grill should be relatively clean at all times," writes grilling guru Steven Raichlen in "The Barbecue Bible." "Clean grates are essential for killer grill marks, and they help keep food from sticking."
His mantra: "Keep it hot, clean and lubricated." Here's how to do just that:
Do a seasonal check-up
Don't remember what you did at the end of last year? Not sure what happened under your grill cover all winter? Before you turn anything on, give your grill the once-over. For a charcoal grill, Raichlen recommends scraping out the ash from the firebox if you didn't at the end of your last grilling season.
For a gas grill, Raichlen says you should clean the drip pans, if needed. Remove the grates and the baffle plates that help direct grease away from the burner tubes. Then make sure nothing (spiders, spider webs, other organic material) is blocking the burner tubes. If flames don't come out of all the holes in the tubes, you'll need to clear the obstruction with something like a bent paper clip or thin wire. Make sure your igniter is working and you hear a click and see a spark.
Turn on the heat
"Preheating is a must, and it also is the first step in cleaning the grill," says Elizabeth Karmel, the chef and author of GirlsattheGrill.com and four cookbooks, most recently "Steak and Cake." "Think of it as a sterilization process." For a gas grill, turn the burners to high for 10 minutes; likewise, let your charcoal grill preheat with the lid on and vents open for 10 minutes. This will help burn off anything left over from your last grill session.
Scrub the grate
Some suggest scrubbing grills with a ball of crumpled foi. Photo for The Washington Post by Tom McCorkle
Now that any residual food has been charred, it's time to get rid of it. Karmel suggests scrubbing with a ball of crumpled foil (about the size of a navel orange) held in a pair of long-handled tongs. That's an especially good option for people worried about stray bristles from wire brushes, but if you have a metal brush you trust, by all means use it. In his book "Project Fire," Raichlen says to look for a wire brush with bristles anchored in a twisted wire coil.
Oil the grate (or the food)
This is a combined cleaning and prep step, and it's also a bit contentious. Many grilling experts recommend oiling the grate before loading it up with food. Others argue that the oil residue can build up and actually cause food to stick.
If you're oiling the grates: With the grill still on high heat, brush the grates with an oiled wad of paper towels held in that trusty pair of tongs. This will catch any bits of food you didn't scrape off, as well as grease the grates so the food won't stick, much as when you add fat to a pan on the stove top. Be sure you use an oil that can handle high heat. Raichlen says grapeseed and the cheaper canola are good bets.