You'll see in your Human Design chart that there are 9 centers.
The centers that are COLORED IN are called "Defined", "closed" or "fixed". Having a center defined means that you have a specific and consistent way of processing and experiencing that kind of energy in your life. Your Defined Centers are your strengths. These are the parts of your designed energy you were born with.

The WHITE CENTERS are called "Open or undefined". When you have a center Open it means that you don’t have a fixed or consistent way of processing and experiencing that particular energy.

Open centers are our greatest teachers and deepest source of wisdom. An Open center takes in and amplifies that center’s specific energy. So our experience and understanding of the energy in that Open center is unlimited.

HOWEVER,

Open Centers present great opportunities for us but also great challenges. Here is where we are “conditioned” (deeply influenced) by those around us, like parents, siblings, friends, parents, teachers, etc., as well as by our society’s “norms” and expectations.

Open Centers are where we experience and carry our deepest pain because we think those energies coming IN to us are “ours”, i.e. something we ourselves have generated. But they are not.

This can be very confusing because those energies coming into our Open Centers change depending on whom we are with. We may question our value, our lovability, our commitment, or our resolve (or even our sanity!) because we seem to be so inconsistent in those Open areas of our lives. But, open centers are also our greatest gift, because we can pick up on other people's energies and tune into our empathy here. So they are our deepest empathic centers as well.

But if we are unaware of the conditioning we receive in these centers, which comes from outside of us, we will be pulled away from Who We Truly Are and from our Authentic Expression of ourselves. That's why "de-conditioning" is so important.