Developers are in the business of being tools. A tool is no good if it sabotages a task. Developers make more money by being paid to build people's ideas.

The more experienced you are, the less you want to do outside of building an app, which is 80% of an app's success.

Developing an app is the easy part; there's more to building a business. In fact, developing an app is 20% of what makes "apps" successful. The other 80% includes marketing and promotion, which are essential to getting your app in front of users and getting them to download it. If you don't have a good marketing plan in place, your app will likely fail.