Protection is the main reason. With metal on both sides of every stone, the diamond edges are shielded from knocks, and the ring keeps a clean, even surface. The look is tailored rather than glittery: a neat line of light framed by polished rails.
They also behave well next to an engagement ring. With no prongs on the band itself, there is less to catch on the ring beside it or to rub against its metal day after day.
If you type, cook, garden or lift all day, a channel band is one of the easiest diamond rings to forget you are wearing. Nothing sticks up to catch on gloves, hair or knitwear, and the stones sit below the rim of the metal. It is the same thinking behind bezel engagement rings, which suit active hands because metal surrounds the stone instead of reaching over it.
Nurses, teachers, parents of small children and anyone who washes their hands often tend to appreciate that smoothness most, since a band without prongs is simply easier to keep on all day.
Pave shows more diamond, and channel guards it better. In a pave band, small stones sit near the surface under tiny beads of metal, so light reaches them from the sides and the effect is brighter. In a channel band, the walls cover the stone edges and block a little of that light. Bezel set diamonds face the same tradeoff, showing slightly less light than prongs do.
Choose channel if security and a smooth feel matter more to you than maximum sparkle. Choose pave if you want as much glitter as possible and your hands are gentle on rings.
Look at where the two rings meet. A straight channel band can leave a small gap under some engagement ring heads, so check the pair from the side before you buy. Match the metal and keep the widths close, and the crisp edges of the channel will line up neatly with the shank of your ring.
If the diamonds run the whole way round, the band follows the same rule as any eternity band: a full circle is hard or impossible to resize, so get the size right first with the free ring sizer Rare Carat will send you. To plan both rings together, start with the engagement rings and choose the wedding ring to suit it.