Mark 1234 and Skyhawk N are both correct; it's to check that it's working, it's also to ensure the carb ice is removed prior to beginning the takeoff roll.
Don't assume that the procedures for one airplane apply to all airplanes, or more specifically, simply because this or that is the way you've done it before, you should do it that way all the time.
Apply carb heat where you need it, when you need it.
Simply because you're not normally recommended as needing it during a go-around, for example doesn't mean you won't need it. I've had engines quit as I or a student executed a go-around, with power restored by the application of carburetor heat.
Use it when you need it.