Name Your Price is a feature that lets you pay above the listed price for a release if you want to give an artist extra support.
When an artist has enabled Pay More Pricing, you'll see a price field at checkout pre-filled with the listed price (or your member price if you're a co-op member). You can leave it as is or enter any higher amount you choose.
Any amount above the listed price goes directly to the artist and shows up as "Extra Artist Support" in your checkout summary and on the post-purchase confirmation screen.
There's no obligation to pay more - the listed price is always the minimum.