I have released two courses within the past year.
The second one was just last week and only to a small email list of only 200 people.
I also tweeted to my 2300 followers.
I’ve made 45 sales in that time.
I agree that marketing is a big part of it.
But, most importantly, market research and copywriting are the big indicators of how well your product will sell.
Never build a product because you THINK your audience will want it.
You need to validate the offer first and then assemble exactly what your audience wants.
You need to write compelling sales copy and email copy to sell the thing you know they want.
No way around that.