Dan Norman's classic The Design of Everyday Things goes into great detail about the idea of affordances. You can think of this as the idea that how something looks suggests ways in which it can be used.
Good affordances make things intuitive and easy to use. Negative affordances get in the way by suggesting inappropriate uses. The classic example is door handles - a loop handle affords pulling, so if the door actually needs to be pushed then that's bad design. A push plate helps to avoid misunderstanding.
I love this example because it's so everyday, something we all use on a regular basis, but probably never notice (unless we meet a poorly designed door). That's what people mean when they say "good design should be invisible".
Well-designed products and experiences feel intuitive in use, but that doesn't mean that they're easy to arrive at. It requires effective design thinking, grounded in a solid understanding of customers, to design experiences that work easily for people.
We'd suggest mapping your customer journey to find out where customers are hitting roadblocks, and looking for ways to improve the design of your experience so that what feels natural is the right thing to do.