Glory
Unlike power or fame, glory is a pretty big deal for sculptors. After all, like most fine artists, you've made a thing (or a bunch of things). Like many others, your work is commissioned or otherwise bought for public or semi-private display, which is pretty glorious itself.
While a painter might get the odd mural to paint on the side of a business, you might have the opportunity to create a symbol for millions of people right in front of city hall. Thinking about the foot traffic alone should be enough to get you molding. However, unlike painters, or actors, or poets, your physical work can last for ages, maybe even for-freaking-ever.
Think about it: what do we have left over from the ancient Egyptians? We have hieroglyphics, but can you read those? We have pyramids too, but you'll never live in one. So what's left for you to enjoy from the literally thousands of years of Egyptian creativity and innovation? Dozens of obelisks, dozens more statues, and one giant lady lion near the banks of the Nile.