The extent that subliminal messages work is debatable. It partly comes down to the person, and partly comes down to realistic expectations.
An easy example is product placement in movies and shows. These items are so commonplace to most people, they are not really even noticed. But seeing the items might make a person either want that brand and product, as they're thinking about it, or makes them want the general type of product. This has been found to result in two things: Firstly, it has been found that people are more likely to buy the most recent thing they've seen in a show or movie rather than a commercial. Secondly, at a movie theater, it helps drive snack and drink sales.
I also think this brief list of scenarios demonstrates another good point: When they work, subliminal messages are about adjusting or controlling behaviors, and definitely not about any physical shift of any sort. A recording with subliminal messages cannot do things like make moles or warts vanish, and definitely cannot change a person into anything or anyone other than they currently are.