Co-ordinating fabrics is a skill and, just like any skill, not everyone excels at it. It's also subjective - we all have different tastes. However, there are certain combinations which appeal almost universally. Some people just have the knack of knowing what fabric combinations work well.
I'm not one of those lucky people. I have to work at getting the right fabrics for a project. The good news is that with practice, your skills at choosing fabrics will improve.