As well as the engineer producer and musician producer there is a third type which I shall call the 'executive producer'.
The executive producer doesn't know anything about engineering nor about music. "So how do they produce?", you ask.
The answer is that they know all the people they need with the technical and musical skills to handle all the elements of production, and most importantly, they know when something sounds right. They don't need to be present all the time in the studio, they just need to hear work in progress occasionally. Their instinct will tell them whether the product is marketable or not.
Nice work if you can get it, you may say, and I suppose it must be. DJs often find their way into production along this route, because they are in a better position than anyone else in the industry to know what will and what will not please an audience.
The difference between something that sells and something that ends up on a cut price market stall may be incredibly small, but at least in dance music, the DJ will be able to recognise that difference.