In many countries, corporate profits are taxed at a corporate tax rate, and dividends paid to shareholders are taxed at a separate rate. Such a system is sometimes referred to as "double taxation", because any profits distributed to shareholders will eventually be taxed twice.
One solution to this (as in the case of the Australian and UK tax systems) is for the recipient of the dividend to be entitled to a tax credit, which addresses the fact that the profits represented by the dividend have already been taxed. The company profit being passed on is therefore effectively only taxed at the rate of tax paid by the eventual recipient of the dividend.
In other systems, dividends are taxed at a lower rate than other income (for example, in the US) or shareholders are taxed directly on the corporation's profits and dividends are not taxed. For example, S corporations in the US do not pay any federal income taxes. Instead, the corporation's income or losses are divided among and passed through to its shareholders. The shareholders must then report the income or loss on their own individual income tax returns.
Another disadvantage of corporations is that, as Adam Smith pointed out in the Wealth of Nations, when ownership is separated from management (i.e. the actual production process required to obtain the capital), the latter will inevitably begin to neglect the interests of the former, creating dysfunction within the company. Some maintain that recent events in corporate America may serve to reinforce Smith's warnings about the dangers of legally-protected, collectivist hierarchies.
The fees and legal costs required to form a corporation may be substantial, especially if the business is just being started and the corporation is low on financial resources.