English: It shows a bad conversion from raster image to vector image. The word "you" above is raster image, the one below is vector image converted from the raster to path text. As you can see, although vector image is scalable and considered to have better quality, the detail of the shape could be lost during the vectorization. The lose of detail depends on the technique the user uses for vectorization, but a 100% perfect vectorization is generally very hard, or almost impossible, to achieve. Be very careful when you vectorize a raster image.
The quality of a coversion to embedded text depends on the used font.

And you can see when you reasonably enlarge the image, the raster image's quality is quite acceptable, while the path text image is not acceptable because of losing details.