Vectorization is useful when a logo, icon, or flat illustration must scale without pixelation. Begin with the cleanest high-contrast original available and inspect the paths produced by the image vectorizer.
Check both small and large display sizes. Too many points can make a shape lumpy or hard to edit; aggressive simplification can erase details. Test colors, transparent areas, and the exported file in another viewer. A photograph full of texture is usually better kept as a raster image.
The goal is editable, accurate shapes, not merely an SVG file extension.