You just flip the handle over and press the little nubbins backwards through the holes to push out the woody gunk into the trash. If it doesn’t fall completely out a gentle whack on the side of the can knocks it out. It’s all fibrous and doesn’t have much flavor.
Mine goes in the dishwasher after you reverse-press the fibers into the trash. I do peel the garlic first.
Now to be fair, I hate chunks of garlic, I just want some garlic flavor in the food if it’s supposed to be there. So I’m never going to just smash or coarsely chop it. I’m also a garlic-sweater so I don’t use garlic at all if it isn’t necessary for the dish. But some delicious foods require it, and I just have to try to plan them so I don’t have something important the next day.