For a startup, people use your product because they have a problem to solve. It does not matter how bad your UI/UX is, how drastically bad your flows are, if you are offering a solution no one else is, you will have users. It just needs to work.
It's funny because I came to the same conclusion years ago, but had not written it until yesterday in a different context:
I came to the conclusion the hard way when I focused on UI/UX (it should look good) instead of focusing on providing the best possible solution. This is the most important learning I took from the entire entrepreneurial experience.