While the perforated plate may seem like it's helping, it's easier to take the shaker tops off so you can get a spoon in the jar to measure the amount of spice you need accurately.
Adding seasoning multiple times while cooking helps build a dish's flavor, but as the tiny holes release a small amount of spice, removing the sifter allows you to season properly.
If you want to sprinkle spices on dishes, put a few tablespoons on a handheld cocktail sieve, hold it over your food, and tap the edge of the tool with the backside of a knife.