Sigma 18-200mm F3.5-6.3 DC OS HSM
This isn't a lens for pixel-peepers who above all else demand critical corner-to-corner sharpness in every shot. But for more normal users looking for a versatile, all-in-one travel lens within a budget, and who'd prefer to while away their evenings looking at and sharing their images rather than post-processing them, it fits the bill just fine.
Travel and everyday use, where versatility of framing and portability are more important than maximum image quality.
More demanding work, where the need for optical quality outweighs more practical concerns.