So why does this happen exactly? I can't say for certain, but I have a few ideas. For fun, I'm going to start to build a list. Here's my first pass:
- People think marketing is easy. There are no visible formulas, no complex math calculations, no obvious structure that the outside observer might look at, become intimidated, and think, "I have no understanding of what is going here. If I comment without understanding, I will look like an idiot."
- People confuse process execution with actual understanding. For many people, it's easy to learn process. By following steps, like a recipe, they can repeat a pattern faithfully and precisely without ever scratching the surface to get to the underlying why that glues it together. Many teachers/schools/education tracks also reinforce process over understanding.
- Marketing does not follow a straightforward formula of process equals result. A simple example of this -- Hollywood has a "factory" designed around building successful movies, but they still manage to produce a significant volume of movies that totally suck.
- Many people have a difficult time observing complex, multi-threaded dynamic systems and predicting results. Here's an example -- imagine driving to work, piloting your vehicle in traffic. As you travel, you're controlling your car, you're also interpreting what other drivers are going to do with their vehicle. Safe driving requires sorting through the patterns of vehicles and predicting behavior, then adapting your intended path to travel safely and efficiently through the traffic. Now imagine those drivers that seem to pilot their vehicle like their unaware of other vehicles. Traffic has the potential to be very complex, so we impose a system of rules to make the behavior predictable, but markets, products and people aren't bound by those same rigid rules.
- People confuse marketing with universalizing their own tastes, not developing an empathetic understanding of others. We all wind up dancing with this issue from time to time -- meals at The French Laundry have to conform to Thomas Keller's sense of what tastes good. But when you're targeting an audience, you're using your ruler to ensure that it was built to that planned audience, not merely a projection of you.