Why does my logo look blurry when I enlarge it?
The recipe and the photograph
A useful way to hold the difference: a vector file is a recipe — points, curves, fills, and instructions for drawing them. A raster file is a photograph of the finished cake. You can enlarge a recipe's output to any size; you cannot enlarge a photograph without inventing detail.
This is why a printer asks for "the vector file" and is unimpressed by a very large PNG. Size in pixels is not the point. A 4000-pixel logo is still a photograph.
When to use which
Vector for anything made of shapes and text: logos, icons, illustrations, diagrams, and anything that will be printed at a size you cannot predict. Raster for photographs, which have no shapes to describe.
Converting a photo to vector produces a stylised approximation, not a sharper photo. It is a creative effect, not a repair.
Why some SVG files are enormous
Usually too many anchor points. Auto-traced artwork can contain thousands of nodes where a hand-drawn version would use dozens — and every node is text in the file. The other culprit is a raster image embedded inside the SVG, which defeats the point entirely: you now have a pixel image wrapped in vector packaging.
The practical habit
Keep the editable source and treat exports as disposable. The day you need the logo at billboard size, or in one colour for embroidery, or with the wordmark removed, the source is the only thing that helps. Exports are answers to yesterday's question.
