Do you always start a complex 3D part as a solid?

[indiancad]

For simple mechanical parts, starting with a 3D solid is usually straightforward.

But for parts with complex curved geometry, I sometimes find it cleaner to build the shape as surfaces first and then convert/thicken the result into a solid.

The advantage is that the surface geometry can be controlled independently before committing to the final solid form.

I’m curious how others approach this:

For complex curved parts, do you prefer a solid-first or surface-first workflow—and why?