What would happened if fish had no scales?

Theyre are jellyfish and starfish to name a couple that do quite well without fins. Then there are all the shellfish too. I wonder though if you meant what would have happened if fish had evolved without fins. If that is the case then the best answer I can give is that life as we know it would not exist because fins were the beginning of legs/limbs. No fins = no legs = differently evolved species.

Jellyfish, starfish and shellfish are not fish. They belong in different families and are not related to fish. The person above has no idea of what he or she is talking about.