A ring looks like one solid object, but it's really an assembly of parts, each with its own job, and each with its own wear pattern over time. Understanding the anatomy helps you understand why your jeweler recommends what they do.
The shank is the band itself. Its thickness at the bottom, opposite the stone, matters more than people realize; a thin shank on a ring worn daily for years can genuinely wear through, especially in soft metals like 18kt gold. The head or basket is what actually holds your center stone, supported by prongs, or claws, that grip the stone at its edges. Prongs are the single most common point of failure I see, they thin out from years of contact with clothing, hair, and countertops, and a loose stone almost always starts with a worn prong.
Underneath the stone sits the gallery, the open architecture that lets light into the diamond from below. A taller gallery looks elegant but sits higher off the finger, meaning more exposure to knocks. And wherever two pieces of metal are joined, at the shoulders, at a split shank, anywhere a repair has happened, that solder joint is a slightly weaker point than the surrounding metal.
My standing advice after years around the bench: get prongs checked every six to twelve months, especially on rings worn daily. It takes a jeweler under a minute with a loupe, and it's the cheapest insurance you'll ever buy against losing a stone.