The course you showed this time looks like a good course, although I know nothing about that topic. However, it was published only last month. It takes time. You don't build an audience over night.
We were all new instructors at one point. It took me at least two years and six or seven courses before I was making any significant money. I also went back and completely re-recorded my first two courses because I realized how bad they were and I had learned a lot about creating quality videos.
Look carefully at this graph of my earnings. The actual numbers are not important. But look how long it took me to get decent results. I worked at it over time. I didn't quit after a month of not getting sales. Don't tell me to do research or try to tell me how Udemy works. I have been studying how the Udemy system works for almost five years.
