Before LLCs were legally able to be established, the practical ways to organize businesses was to establish either a corporation or limited partnership. 

Limited partnerships are cumbersome to maintain are are confusing when compared to LLCs. 

There can be some legitimate reasons for a new business to organize as a corporation instead of an LLC for tax purposes. When organizing a new business, caution should be exercised to be sure that the business is being established in the best way possible.