Paying For Founder IP
The Intellectual Property (IP) created by the company's founders has real value. For that reason, it's important to transfer ownership of the IP from the individual founder to the company through an IP Assignment Agreement. But in order to complete that transfer of IP, the company needs to provide some payment or compensation to the founder in exchange.
Usually, founders don't expect to profit from assigning IP to their company. It's a legal formality that benefits the company and, over the long-term, will benefit the founder too. So it's quite common for the company to pay a nominal amount, like $5 or $10, to complete the IP assignment and transfer ownership to the company.