A corporation has its own assets that are invested by its owners. Since the corporation is regarded as a legal person, all its business transactions only affect the corporation’s assets. While the founders did have to invest their own assets (to start it or at another time), corporations offer the strongest protection to its owners from personal liability. This means that the total assets of the owners are not at risk, should the business declare insolvency. Not least, this risk mitigation helps strengthen the willingness to invest.
There are also disadvantages to this low risk corporate model. Generally speaking, corporate owners get dividends, because they are regarded as shareholders. However, many growing companies don’t give dividends but inject profits back into the corporation to promote further growth.
In the US tax code, S corporations do not pay corporate income taxes on profits. Instead, the profits are allocated to shareholders according to their stake in the company, and the shareholders report those profits as taxable income on their personal returns.