Satellite (you probably mean "aerial", commercially avaliable satellite imagery just doesn't have enough resolution) is perhaps map imagery, a supplementary source for maps; but not map data at all: maps are an interpretation of the world, imagery is "just" raw pictures.
For example, my city gets aerial imagery taken ~yearly, with resolution better than 1 ft/px. This is very precise, and the updates are frequent; yet, still insufficient to answer typical mapping questions, such as "can I get there from here, using this vehicle?" That's what a map should be able to answer: both map and aerial image can tell you "there is a vehicular track", but only the map will tell you "and it's private, and even if you don't care for signs, this gate over here is locked, so no, this does not route; you can't go over that road here, as it has a bollard in the middle; that bridge is too flimsy for you; that street is one-way but opposite; you need to go that way, but there's toll collected; otherwise, there's a lengthy detour."
Only some of these features can be inferred from an image. (Of course, the map needs to be kept up-to-date with all this data, but that's a very different story)
For example, my city gets aerial imagery taken ~yearly, with resolution better than 1 ft/px. This is very precise, and the updates are frequent; yet, still insufficient to answer typical mapping questions, such as "can I get there from here, using this vehicle?" That's what a map should be able to answer: both map and aerial image can tell you "there is a vehicular track", but only the map will tell you "and it's private, and even if you don't care for signs, this gate over here is locked, so no, this does not route; you can't go over that road here, as it has a bollard in the middle; that bridge is too flimsy for you; that street is one-way but opposite; you need to go that way, but there's toll collected; otherwise, there's a lengthy detour."
Only some of these features can be inferred from an image. (Of course, the map needs to be kept up-to-date with all this data, but that's a very different story)