Second, incorporation does not protect the business, it protects investors. Without it, investors would be general partners and would be personally liable for anything the business does, including all debts and torts, even if they had no active role in running the business.
Third, where owners of a corporation or LLC do participate in running a business, they often can be held personally liable for the debts and torts of the business. This is called “piercing the corporate veil” and happens all the time in lawsuits against small businesses.