Important diiference to note: there is "play" punishment and there is actual punishment.

In role play, you might find it fun to be "punished" for dressing in a slutty outfit, but the punishment administered is understood by both parties to be play and not a learning experience. It's simply a spicy way to lead into a cropping, spanking or humiliation play.

Actual punishment is not supposed to be an activity the one being punished enjoys. If you like spankings, then punishment would be more effective if it were something like getting denied play spankings for a few days or so. If you're late by 20 minutes, punishment might be waking up twenty minutes earlier than you're used to each morning to make your Dom coffee or bring him breakfast in bed etc. Something that makes you aware of your indiscretion and gets you to thinking about how you won't do it again.